Methods

43 files changed, 1041 insertions, 563 deletions

diff --git a/Cargo.lock b/Cargo.lock
index b4fd7b72..dcf7bfdf 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -335,6 +335,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "lock_api"
+version = "0.4.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "88943dd7ef4a2e5a4bfa2753aaab3013e34ce2533d1996fb18ef591e315e2b3b"
+dependencies = [
+ "scopeguard",
+]
+
+[[package]]
 name = "log"
 version = "0.4.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -449,6 +458,29 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "da32515d9f6e6e489d7bc9d84c71b060db7247dc035bbe44eac88cf87486d8d5"
 
 [[package]]
+name = "parking_lot"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "87f5ec2493a61ac0506c0f4199f99070cbe83857b0337006a30f3e6719b8ef58"
+dependencies = [
+ "lock_api",
+ "parking_lot_core",
+]
+
+[[package]]
+name = "parking_lot_core"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "28141e0cc4143da2443301914478dc976a61ffdb3f043058310c70df2fed8954"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "redox_syscall",
+ "smallvec",
+ "windows-sys",
+]
+
+[[package]]
 name = "pdf-writer"
 version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -652,6 +684,12 @@ dependencies = [
 ]
 
 [[package]]
+name = "scopeguard"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
+
+[[package]]
 name = "serde"
 version = "1.0.136"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -819,6 +857,7 @@ dependencies = [
  "memmap2",
  "miniz_oxide 0.4.4",
  "once_cell",
+ "parking_lot",
  "pdf-writer",
  "pico-args",
  "pixglyph",
@@ -967,6 +1006,49 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 
 [[package]]
+name = "windows-sys"
+version = "0.32.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3df6e476185f92a12c072be4a189a0210dcdcf512a1891d6dff9edb874deadc6"
+dependencies = [
+ "windows_aarch64_msvc",
+ "windows_i686_gnu",
+ "windows_i686_msvc",
+ "windows_x86_64_gnu",
+ "windows_x86_64_msvc",
+]
+
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.32.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d8e92753b1c443191654ec532f14c199742964a061be25d77d7a96f09db20bf5"
+
+[[package]]
+name = "windows_i686_gnu"
+version = "0.32.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6a711c68811799e017b6038e0922cb27a5e2f43a2ddb609fe0b6f3eeda9de615"
+
+[[package]]
+name = "windows_i686_msvc"
+version = "0.32.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "146c11bb1a02615db74680b32a68e2d61f553cc24c4eb5b4ca10311740e44172"
+
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.32.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c912b12f7454c6620635bbff3450962753834be2a594819bd5e945af18ec64bc"
+
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.32.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "504a2476202769977a040c6364301a3f65d0cc9e3fb08600b2bda150a0488316"
+
+[[package]]
 name = "xi-unicode"
 version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/Cargo.toml b/Cargo.toml
index ed265b1a..e30971bd 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -20,6 +20,7 @@ fxhash = "0.2"
 once_cell = "1"
 serde = { version = "1", features = ["derive"] }
 typed-arena = "2"
+parking_lot = "0.12"
 
 # Text and font handling
 hypher = "0.1"
diff --git a/src/eval/args.rs b/src/eval/args.rs
index 67da9865..40454ff5 100644
--- a/src/eval/args.rs
+++ b/src/eval/args.rs
@@ -1,6 +1,6 @@
 use std::fmt::{self, Debug, Formatter, Write};
 
-use super::{Cast, Value};
+use super::{Array, Cast, Dict, Value};
 use crate::diag::{At, TypResult};
 use crate::syntax::{Span, Spanned};
 use crate::util::EcoString;
@@ -147,6 +147,23 @@ impl Args {
         Ok(())
     }
 
+    /// Extract the positional arguments as an array.
+    pub fn to_positional(&self) -> Array {
+        self.items
+            .iter()
+            .filter(|item| item.name.is_none())
+            .map(|item| item.value.v.clone())
+            .collect()
+    }
+
+    /// Extract the named arguments as a dictionary.
+    pub fn to_named(&self) -> Dict {
+        self.items
+            .iter()
+            .filter_map(|item| item.name.clone().map(|name| (name, item.value.v.clone())))
+            .collect()
+    }
+
     /// Reinterpret these arguments as actually being an array index.
     pub fn into_index(self) -> TypResult<i64> {
         self.into_castable("index")
diff --git a/src/eval/array.rs b/src/eval/array.rs
index 2da1a5f4..6fb278e3 100644
--- a/src/eval/array.rs
+++ b/src/eval/array.rs
@@ -3,9 +3,11 @@ use std::fmt::{self, Debug, Formatter, Write};
 use std::ops::{Add, AddAssign};
 use std::sync::Arc;
 
-use super::Value;
-use crate::diag::StrResult;
+use super::{Args, Func, Value};
+use crate::diag::{At, StrResult, TypResult};
+use crate::syntax::Spanned;
 use crate::util::ArcExt;
+use crate::Context;
 
 /// Create a new [`Array`] from values.
 #[allow(unused_macros)]
@@ -66,36 +68,134 @@ impl Array {
         Arc::make_mut(&mut self.0).push(value);
     }
 
+    /// Remove the last value in the array.
+    pub fn pop(&mut self) -> StrResult<()> {
+        Arc::make_mut(&mut self.0).pop().ok_or_else(|| "array is empty")?;
+        Ok(())
+    }
+
+    /// Insert a value at the specified index.
+    pub fn insert(&mut self, index: i64, value: Value) -> StrResult<()> {
+        let len = self.len();
+        let i = usize::try_from(index)
+            .ok()
+            .filter(|&i| i <= self.0.len())
+            .ok_or_else(|| out_of_bounds(index, len))?;
+
+        Arc::make_mut(&mut self.0).insert(i, value);
+        Ok(())
+    }
+
+    /// Remove and return the value at the specified index.
+    pub fn remove(&mut self, index: i64) -> StrResult<()> {
+        let len = self.len();
+        let i = usize::try_from(index)
+            .ok()
+            .filter(|&i| i < self.0.len())
+            .ok_or_else(|| out_of_bounds(index, len))?;
+
+        Arc::make_mut(&mut self.0).remove(i);
+        return Ok(());
+    }
+
     /// Whether the array contains a specific value.
     pub fn contains(&self, value: &Value) -> bool {
         self.0.contains(value)
     }
 
-    /// Clear the array.
-    pub fn clear(&mut self) {
-        if Arc::strong_count(&self.0) == 1 {
-            Arc::make_mut(&mut self.0).clear();
-        } else {
-            *self = Self::new();
+    /// Extract a contigous subregion of the array.
+    pub fn slice(&self, start: i64, end: Option<i64>) -> StrResult<Self> {
+        let len = self.len();
+        let start = usize::try_from(start)
+            .ok()
+            .filter(|&start| start <= self.0.len())
+            .ok_or_else(|| out_of_bounds(start, len))?;
+
+        let end = end.unwrap_or(self.len());
+        let end = usize::try_from(end)
+            .ok()
+            .filter(|&end| end <= self.0.len())
+            .ok_or_else(|| out_of_bounds(end, len))?;
+
+        Ok(Self::from_vec(self.0[start .. end].to_vec()))
+    }
+
+    /// Transform each item in the array with a function.
+    pub fn map(&self, ctx: &mut Context, f: Spanned<Func>) -> TypResult<Self> {
+        Ok(self
+            .iter()
+            .cloned()
+            .map(|item| f.v.call(ctx, Args::from_values(f.span, [item])))
+            .collect::<TypResult<_>>()?)
+    }
+
+    /// Return a new array with only those elements for which the function
+    /// return true.
+    pub fn filter(&self, ctx: &mut Context, f: Spanned<Func>) -> TypResult<Self> {
+        let mut kept = vec![];
+        for item in self.iter() {
+            if f.v
+                .call(ctx, Args::from_values(f.span, [item.clone()]))?
+                .cast::<bool>()
+                .at(f.span)?
+            {
+                kept.push(item.clone())
+            }
         }
+        Ok(Self::from_vec(kept))
     }
 
-    /// Iterate over references to the contained values.
-    pub fn iter(&self) -> std::slice::Iter<Value> {
-        self.0.iter()
+    /// Return a new array with all items from this and nested arrays.
+    pub fn flatten(&self) -> Self {
+        let mut flat = vec![];
+        for item in self.iter() {
+            if let Value::Array(nested) = item {
+                flat.extend(nested.flatten().into_iter());
+            } else {
+                flat.push(item.clone());
+            }
+        }
+        Self::from_vec(flat)
     }
 
-    /// Extracts a slice of the whole array.
-    pub fn as_slice(&self) -> &[Value] {
-        self.0.as_slice()
+    /// Return the index of the element if it is part of the array.
+    pub fn find(&self, value: Value) -> Option<i64> {
+        self.0.iter().position(|x| *x == value).map(|i| i as i64)
+    }
+
+    /// Join all values in the array, optionally with separator and last
+    /// separator (between the final two items).
+    pub fn join(&self, sep: Option<Value>, mut last: Option<Value>) -> StrResult<Value> {
+        let len = self.0.len();
+        let sep = sep.unwrap_or(Value::None);
+
+        let mut result = Value::None;
+        for (i, value) in self.iter().cloned().enumerate() {
+            if i > 0 {
+                if i + 1 == len {
+                    if let Some(last) = last.take() {
+                        result = result.join(last)?;
+                    } else {
+                        result = result.join(sep.clone())?;
+                    }
+                } else {
+                    result = result.join(sep.clone())?;
+                }
+            }
+
+            result = result.join(value)?;
+        }
+
+        Ok(result)
     }
 
     /// Return a sorted version of this array.
     ///
     /// Returns an error if two values could not be compared.
-    pub fn sorted(mut self) -> StrResult<Self> {
+    pub fn sorted(&self) -> StrResult<Self> {
         let mut result = Ok(());
-        Arc::make_mut(&mut self.0).sort_by(|a, b| {
+        let mut vec = (*self.0).clone();
+        vec.sort_by(|a, b| {
             a.partial_cmp(b).unwrap_or_else(|| {
                 if result.is_ok() {
                     result = Err(format!(
@@ -107,7 +207,7 @@ impl Array {
                 Ordering::Equal
             })
         });
-        result.map(|_| self)
+        result.map(|_| Self::from_vec(vec))
     }
 
     /// Repeat this array `n` times.
@@ -119,6 +219,17 @@ impl Array {
 
         Ok(self.iter().cloned().cycle().take(count).collect())
     }
+
+    /// Extract a slice of the whole array.
+    pub fn as_slice(&self) -> &[Value] {
+        self.0.as_slice()
+    }
+
+
+    /// Iterate over references to the contained values.
+    pub fn iter(&self) -> std::slice::Iter<Value> {
+        self.0.iter()
+    }
 }
 
 /// The out of bounds access error message.
diff --git a/src/eval/dict.rs b/src/eval/dict.rs
index 9127b2eb..b630fc63 100644
--- a/src/eval/dict.rs
+++ b/src/eval/dict.rs
@@ -3,9 +3,11 @@ use std::fmt::{self, Debug, Formatter, Write};
 use std::ops::{Add, AddAssign};
 use std::sync::Arc;
 
-use super::Value;
-use crate::diag::StrResult;
+use super::{Args, Array, Func, Value};
+use crate::diag::{StrResult, TypResult};
+use crate::syntax::Spanned;
 use crate::util::{ArcExt, EcoString};
+use crate::Context;
 
 /// Create a new [`Dict`] from key-value pairs.
 #[allow(unused_macros)]
@@ -56,14 +58,22 @@ impl Dict {
         Arc::make_mut(&mut self.0).entry(key).or_default()
     }
 
+    /// Whether the dictionary contains a specific key.
+    pub fn contains(&self, key: &str) -> bool {
+        self.0.contains_key(key)
+    }
+
     /// Insert a mapping from the given `key` to the given `value`.
     pub fn insert(&mut self, key: EcoString, value: Value) {
         Arc::make_mut(&mut self.0).insert(key, value);
     }
 
-    /// Whether the dictionary contains a specific key.
-    pub fn contains_key(&self, key: &str) -> bool {
-        self.0.contains_key(key)
+    /// Remove a mapping by `key`.
+    pub fn remove(&mut self, key: EcoString) -> StrResult<()> {
+        match Arc::make_mut(&mut self.0).remove(&key) {
+            Some(_) => Ok(()),
+            None => Err(missing_key(&key)),
+        }
     }
 
     /// Clear the dictionary.
@@ -75,6 +85,29 @@ impl Dict {
         }
     }
 
+    /// Return the keys of the dictionary as an array.
+    pub fn keys(&self) -> Array {
+        self.iter().map(|(key, _)| Value::Str(key.clone())).collect()
+    }
+
+    /// Return the values of the dictionary as an array.
+    pub fn values(&self) -> Array {
+        self.iter().map(|(_, value)| value.clone()).collect()
+    }
+
+    /// Transform each pair in the array with a function.
+    pub fn map(&self, ctx: &mut Context, f: Spanned<Func>) -> TypResult<Array> {
+        Ok(self
+            .iter()
+            .map(|(key, value)| {
+                f.v.call(
+                    ctx,
+                    Args::from_values(f.span, [Value::Str(key.clone()), value.clone()]),
+                )
+            })
+            .collect::<TypResult<_>>()?)
+    }
+
     /// Iterate over pairs of references to the contained keys and values.
     pub fn iter(&self) -> std::collections::btree_map::Iter<EcoString, Value> {
         self.0.iter()
diff --git a/src/eval/mod.rs b/src/eval/mod.rs
index 2c864036..564dca20 100644
--- a/src/eval/mod.rs
+++ b/src/eval/mod.rs
@@ -19,7 +19,9 @@ mod module;
 mod ops;
 mod scope;
 mod show;
+mod str;
 
+pub use self::str::*;
 pub use args::*;
 pub use array::*;
 pub use capture::*;
@@ -35,6 +37,7 @@ pub use show::*;
 pub use styles::*;
 pub use value::*;
 
+use parking_lot::{MappedRwLockWriteGuard, RwLockWriteGuard};
 use unicode_segmentation::UnicodeSegmentation;
 
 use crate::diag::{At, StrResult, Trace, Tracepoint, TypResult};
@@ -207,9 +210,9 @@ impl Eval for Expr {
             Self::Array(v) => v.eval(ctx, scp).map(Value::Array),
             Self::Dict(v) => v.eval(ctx, scp).map(Value::Dict),
             Self::Group(v) => v.eval(ctx, scp),
-            Self::Call(v) => v.eval(ctx, scp),
+            Self::FuncCall(v) => v.eval(ctx, scp),
+            Self::MethodCall(v) => v.eval(ctx, scp),
             Self::Closure(v) => v.eval(ctx, scp),
-            Self::With(v) => v.eval(ctx, scp),
             Self::Unary(v) => v.eval(ctx, scp),
             Self::Binary(v) => v.eval(ctx, scp),
             Self::Let(v) => v.eval(ctx, scp),
@@ -254,7 +257,7 @@ impl Eval for Ident {
 
     fn eval(&self, _: &mut Context, scp: &mut Scopes) -> EvalResult<Self::Output> {
         match scp.get(self) {
-            Some(slot) => Ok(slot.read().unwrap().clone()),
+            Some(slot) => Ok(slot.read().clone()),
             None => bail!(self.span(), "unknown variable"),
         }
     }
@@ -384,47 +387,62 @@ impl BinaryExpr {
         op: fn(Value, Value) -> StrResult<Value>,
     ) -> EvalResult<Value> {
         let rhs = self.rhs().eval(ctx, scp)?;
-        self.lhs().access(
-            ctx,
-            scp,
-            Box::new(|target| {
-                let lhs = std::mem::take(&mut *target);
-                *target = op(lhs, rhs).at(self.span())?;
-                Ok(())
-            }),
-        )?;
+        let lhs = self.lhs();
+        let mut location = lhs.access(ctx, scp)?;
+        let lhs = std::mem::take(&mut *location);
+        *location = op(lhs, rhs).at(self.span())?;
         Ok(Value::None)
     }
 }
 
-impl Eval for CallExpr {
+impl Eval for FuncCall {
     type Output = Value;
 
     fn eval(&self, ctx: &mut Context, scp: &mut Scopes) -> EvalResult<Self::Output> {
-        let span = self.callee().span();
         let callee = self.callee().eval(ctx, scp)?;
         let args = self.args().eval(ctx, scp)?;
 
         Ok(match callee {
             Value::Array(array) => {
-                array.get(args.into_index()?).map(Value::clone).at(self.span())
+                array.get(args.into_index()?).map(Value::clone).at(self.span())?
             }
 
             Value::Dict(dict) => {
-                dict.get(args.into_key()?).map(Value::clone).at(self.span())
+                dict.get(args.into_key()?).map(Value::clone).at(self.span())?
             }
 
             Value::Func(func) => {
                 let point = || Tracepoint::Call(func.name().map(ToString::to_string));
-                func.call(ctx, args).trace(point, self.span())
+                func.call(ctx, args).trace(point, self.span())?
             }
 
             v => bail!(
-                span,
+                self.callee().span(),
                 "expected callable or collection, found {}",
                 v.type_name(),
             ),
-        }?)
+        })
+    }
+}
+
+impl Eval for MethodCall {
+    type Output = Value;
+
+    fn eval(&self, ctx: &mut Context, scp: &mut Scopes) -> EvalResult<Self::Output> {
+        let span = self.span();
+        let method = self.method();
+        let point = || Tracepoint::Call(Some(method.to_string()));
+
+        Ok(if Value::is_mutable_method(&method) {
+            let args = self.args().eval(ctx, scp)?;
+            let mut receiver = self.receiver().access(ctx, scp)?;
+            receiver.call_mut(ctx, &method, span, args).trace(point, span)?;
+            Value::None
+        } else {
+            let receiver = self.receiver().eval(ctx, scp)?;
+            let args = self.args().eval(ctx, scp)?;
+            receiver.call(ctx, &method, span, args).trace(point, span)?
+        })
     }
 }
 
@@ -527,17 +545,6 @@ impl Eval for ClosureExpr {
     }
 }
 
-impl Eval for WithExpr {
-    type Output = Value;
-
-    fn eval(&self, ctx: &mut Context, scp: &mut Scopes) -> EvalResult<Self::Output> {
-        let callee = self.callee();
-        let func = callee.eval(ctx, scp)?.cast::<Func>().at(callee.span())?;
-        let args = self.args().eval(ctx, scp)?;
-        Ok(Value::Func(func.with(args)))
-    }
-}
-
 impl Eval for LetExpr {
     type Output = Value;
 
@@ -694,13 +701,13 @@ impl Eval for ImportExpr {
         match self.imports() {
             Imports::Wildcard => {
                 for (var, slot) in module.scope.iter() {
-                    scp.top.def_mut(var, slot.read().unwrap().clone());
+                    scp.top.def_mut(var, slot.read().clone());
                 }
             }
             Imports::Items(idents) => {
                 for ident in idents {
                     if let Some(slot) = module.scope.get(&ident) {
-                        scp.top.def_mut(ident.take(), slot.read().unwrap().clone());
+                        scp.top.def_mut(ident.take(), slot.read().clone());
                     } else {
                         bail!(ident.span(), "unresolved import");
                     }
@@ -773,56 +780,85 @@ impl Eval for ReturnExpr {
     }
 }
 
-/// Try to mutably access the value an expression points to.
-///
-/// This only works if the expression is a valid lvalue.
+/// Access an expression mutably.
 pub trait Access {
-    /// Try to access the value.
-    fn access(&self, ctx: &mut Context, scp: &mut Scopes, f: Handler) -> TypResult<()>;
+    /// Access the value.
+    fn access<'a>(
+        &self,
+        ctx: &mut Context,
+        scp: &'a mut Scopes,
+    ) -> EvalResult<Location<'a>>;
 }
 
-/// Process an accessed value.
-type Handler<'a> = Box<dyn FnOnce(&mut Value) -> TypResult<()> + 'a>;
-
 impl Access for Expr {
-    fn access(&self, ctx: &mut Context, scp: &mut Scopes, f: Handler) -> TypResult<()> {
+    fn access<'a>(
+        &self,
+        ctx: &mut Context,
+        scp: &'a mut Scopes,
+    ) -> EvalResult<Location<'a>> {
         match self {
-            Expr::Ident(ident) => ident.access(ctx, scp, f),
-            Expr::Call(call) => call.access(ctx, scp, f),
-            _ => bail!(self.span(), "cannot access this expression mutably"),
+            Expr::Ident(ident) => ident.access(ctx, scp),
+            Expr::FuncCall(call) => call.access(ctx, scp),
+            _ => bail!(self.span(), "cannot mutate a temporary value"),
         }
     }
 }
 
 impl Access for Ident {
-    fn access(&self, _: &mut Context, scp: &mut Scopes, f: Handler) -> TypResult<()> {
+    fn access<'a>(
+        &self,
+        _: &mut Context,
+        scp: &'a mut Scopes,
+    ) -> EvalResult<Location<'a>> {
         match scp.get(self) {
             Some(slot) => match slot.try_write() {
-                Ok(mut guard) => f(&mut guard),
-                Err(_) => bail!(self.span(), "cannot mutate a constant"),
+                Some(guard) => Ok(RwLockWriteGuard::map(guard, |v| v)),
+                None => bail!(self.span(), "cannot mutate a constant"),
             },
             None => bail!(self.span(), "unknown variable"),
         }
     }
 }
 
-impl Access for CallExpr {
-    fn access(&self, ctx: &mut Context, scp: &mut Scopes, f: Handler) -> TypResult<()> {
+impl Access for FuncCall {
+    fn access<'a>(
+        &self,
+        ctx: &mut Context,
+        scp: &'a mut Scopes,
+    ) -> EvalResult<Location<'a>> {
         let args = self.args().eval(ctx, scp)?;
-        self.callee().access(
-            ctx,
-            scp,
-            Box::new(|value| match value {
+        let guard = self.callee().access(ctx, scp)?;
+        try_map(guard, |value| {
+            Ok(match value {
                 Value::Array(array) => {
-                    f(array.get_mut(args.into_index()?).at(self.span())?)
+                    array.get_mut(args.into_index()?).at(self.span())?
                 }
-                Value::Dict(dict) => f(dict.get_mut(args.into_key()?)),
+                Value::Dict(dict) => dict.get_mut(args.into_key()?),
                 v => bail!(
                     self.callee().span(),
                     "expected collection, found {}",
                     v.type_name(),
                 ),
-            }),
-        )
+            })
+        })
     }
 }
+
+/// A mutable location.
+type Location<'a> = MappedRwLockWriteGuard<'a, Value>;
+
+/// Map a reader-writer lock with a function.
+fn try_map<F>(location: Location, f: F) -> EvalResult<Location>
+where
+    F: FnOnce(&mut Value) -> EvalResult<&mut Value>,
+{
+    let mut error = None;
+    MappedRwLockWriteGuard::try_map(location, |value| match f(value) {
+        Ok(value) => Some(value),
+        Err(err) => {
+            error = Some(err);
+            None
+        }
+    })
+    .map_err(|_| error.unwrap())
+}
diff --git a/src/eval/ops.rs b/src/eval/ops.rs
index 6a8f5284..9b46e8f6 100644
--- a/src/eval/ops.rs
+++ b/src/eval/ops.rs
@@ -1,9 +1,8 @@
 use std::cmp::Ordering;
 
-use super::{Dynamic, Value};
+use super::{Dynamic, StrExt, Value};
 use crate::diag::StrResult;
 use crate::geom::{Align, Spec, SpecAxis};
-use crate::util::EcoString;
 use Value::*;
 
 /// Bail with a type mismatch error.
@@ -174,8 +173,8 @@ pub fn mul(lhs: Value, rhs: Value) -> StrResult<Value> {
         (Fractional(a), Float(b)) => Fractional(a * b),
         (Int(a), Fractional(b)) => Fractional(a as f64 * b),
 
-        (Str(a), Int(b)) => Str(repeat_str(a, b)?),
-        (Int(a), Str(b)) => Str(repeat_str(b, a)?),
+        (Str(a), Int(b)) => Str(StrExt::repeat(&a, b)?),
+        (Int(a), Str(b)) => Str(StrExt::repeat(&b, a)?),
         (Array(a), Int(b)) => Array(a.repeat(b)?),
         (Int(a), Array(b)) => Array(b.repeat(a)?),
         (Content(a), Int(b)) => Content(a.repeat(b)?),
@@ -185,16 +184,6 @@ pub fn mul(lhs: Value, rhs: Value) -> StrResult<Value> {
     })
 }
 
-/// Repeat a string a number of times.
-fn repeat_str(string: EcoString, n: i64) -> StrResult<EcoString> {
-    let n = usize::try_from(n)
-        .ok()
-        .and_then(|n| string.len().checked_mul(n).map(|_| n))
-        .ok_or_else(|| format!("cannot repeat this string {} times", n))?;
-
-    Ok(string.repeat(n))
-}
-
 /// Compute the quotient of two values.
 pub fn div(lhs: Value, rhs: Value) -> StrResult<Value> {
     Ok(match (lhs, rhs) {
@@ -358,7 +347,7 @@ pub fn not_in(lhs: Value, rhs: Value) -> StrResult<Value> {
 pub fn contains(lhs: &Value, rhs: &Value) -> Option<bool> {
     Some(match (lhs, rhs) {
         (Value::Str(a), Value::Str(b)) => b.contains(a.as_str()),
-        (Value::Str(a), Value::Dict(b)) => b.contains_key(a),
+        (Value::Str(a), Value::Dict(b)) => b.contains(a),
         (a, Value::Array(b)) => b.contains(a),
         _ => return Option::None,
     })
diff --git a/src/eval/scope.rs b/src/eval/scope.rs
index 19899cae..8acaa431 100644
--- a/src/eval/scope.rs
+++ b/src/eval/scope.rs
@@ -2,7 +2,9 @@ use std::collections::BTreeMap;
 use std::fmt::{self, Debug, Formatter};
 use std::hash::{Hash, Hasher};
 use std::iter;
-use std::sync::{Arc, RwLock};
+use std::sync::Arc;
+
+use parking_lot::RwLock;
 
 use super::{Args, Func, Node, Value};
 use crate::diag::TypResult;
@@ -113,7 +115,7 @@ impl Hash for Scope {
         self.values.len().hash(state);
         for (name, value) in self.values.iter() {
             name.hash(state);
-            value.read().unwrap().hash(state);
+            value.read().hash(state);
         }
     }
 }
@@ -122,7 +124,7 @@ impl Debug for Scope {
     fn fmt(&self, f: &mut Formatter) -> fmt::Result {
         f.write_str("Scope ")?;
         f.debug_map()
-            .entries(self.values.iter().map(|(k, v)| (k, v.read().unwrap())))
+            .entries(self.values.iter().map(|(k, v)| (k, v.read())))
             .finish()
     }
 }
diff --git a/src/eval/str.rs b/src/eval/str.rs
new file mode 100644
index 00000000..3b4349a1
--- /dev/null
+++ b/src/eval/str.rs
@@ -0,0 +1,37 @@
+use super::{Array, Value};
+use crate::diag::StrResult;
+use crate::util::EcoString;
+
+/// Extra methods on strings.
+pub trait StrExt {
+    /// Repeat a string a number of times.
+    fn repeat(&self, n: i64) -> StrResult<EcoString>;
+
+    /// Split this string at whitespace or a specific pattern.
+    fn split(&self, at: Option<EcoString>) -> Array;
+}
+
+impl StrExt for EcoString {
+    fn repeat(&self, n: i64) -> StrResult<EcoString> {
+        let n = usize::try_from(n)
+            .ok()
+            .and_then(|n| self.len().checked_mul(n).map(|_| n))
+            .ok_or_else(|| format!("cannot repeat this string {} times", n))?;
+
+        Ok(self.repeat(n))
+    }
+
+    fn split(&self, at: Option<EcoString>) -> Array {
+        if let Some(pat) = at {
+            self.as_str()
+                .split(pat.as_str())
+                .map(|s| Value::Str(s.into()))
+                .collect()
+        } else {
+            self.as_str()
+                .split_whitespace()
+                .map(|s| Value::Str(s.into()))
+                .collect()
+        }
+    }
+}
diff --git a/src/eval/value.rs b/src/eval/value.rs
index 0e0d08a8..a76b377d 100644
--- a/src/eval/value.rs
+++ b/src/eval/value.rs
@@ -4,10 +4,10 @@ use std::fmt::{self, Debug, Formatter};
 use std::hash::{Hash, Hasher};
 use std::sync::Arc;
 
-use super::{ops, Args, Array, Content, Dict, Func, Layout};
-use crate::diag::{with_alternative, StrResult};
+use super::{ops, Args, Array, Content, Context, Dict, Func, Layout, StrExt};
+use crate::diag::{with_alternative, At, StrResult, TypResult};
 use crate::geom::{Angle, Color, Fractional, Length, Linear, Relative, RgbaColor};
-use crate::syntax::Spanned;
+use crate::syntax::{Span, Spanned};
 use crate::util::EcoString;
 
 /// A computational value.
@@ -120,6 +120,121 @@ impl Value {
             v => Content::Text(v.repr()).monospaced(),
         }
     }
+
+    /// Call a method on the value.
+    pub fn call(
+        &self,
+        ctx: &mut Context,
+        method: &str,
+        span: Span,
+        mut args: Args,
+    ) -> TypResult<Self> {
+        let name = self.type_name();
+        let missing = || Err(missing_method(name, method)).at(span);
+
+        let output = match self {
+            Value::Str(string) => match method {
+                "len" => Value::Int(string.len() as i64),
+                "trim" => Value::Str(string.trim().into()),
+                "split" => Value::Array(string.split(args.eat()?)),
+                _ => missing()?,
+            },
+
+            Value::Array(array) => match method {
+                "len" => Value::Int(array.len()),
+                "slice" => {
+                    let start = args.expect("start")?;
+                    let mut end = args.eat()?;
+                    if end.is_none() {
+                        end = args.named("count")?.map(|c: i64| start + c);
+                    }
+                    Value::Array(array.slice(start, end).at(span)?)
+                }
+                "map" => Value::Array(array.map(ctx, args.expect("function")?)?),
+                "filter" => Value::Array(array.filter(ctx, args.expect("function")?)?),
+                "flatten" => Value::Array(array.flatten()),
+                "find" => {
+                    array.find(args.expect("value")?).map_or(Value::None, Value::Int)
+                }
+                "join" => {
+                    let sep = args.eat()?;
+                    let last = args.named("last")?;
+                    array.join(sep, last).at(span)?
+                }
+                "sorted" => Value::Array(array.sorted().at(span)?),
+                _ => missing()?,
+            },
+
+            Value::Dict(dict) => match method {
+                "len" => Value::Int(dict.len()),
+                "keys" => Value::Array(dict.keys()),
+                "values" => Value::Array(dict.values()),
+                "pairs" => Value::Array(dict.map(ctx, args.expect("function")?)?),
+                _ => missing()?,
+            },
+
+            Value::Func(func) => match method {
+                "with" => Value::Func(func.clone().with(args.take())),
+                _ => missing()?,
+            },
+
+            Value::Args(args) => match method {
+                "positional" => Value::Array(args.to_positional()),
+                "named" => Value::Dict(args.to_named()),
+                _ => missing()?,
+            },
+
+            _ => missing()?,
+        };
+
+        args.finish()?;
+        Ok(output)
+    }
+
+    /// Call a mutating method on the value.
+    pub fn call_mut(
+        &mut self,
+        _: &mut Context,
+        method: &str,
+        span: Span,
+        mut args: Args,
+    ) -> TypResult<()> {
+        let name = self.type_name();
+        let missing = || Err(missing_method(name, method)).at(span);
+
+        match self {
+            Value::Array(array) => match method {
+                "push" => array.push(args.expect("value")?),
+                "pop" => array.pop().at(span)?,
+                "insert" => {
+                    array.insert(args.expect("index")?, args.expect("value")?).at(span)?
+                }
+                "remove" => array.remove(args.expect("index")?).at(span)?,
+                _ => missing()?,
+            },
+
+            Value::Dict(dict) => match method {
+                "remove" => dict.remove(args.expect("key")?).at(span)?,
+                _ => missing()?,
+            },
+
+            _ => missing()?,
+        }
+
+        args.finish()?;
+        Ok(())
+    }
+
+    /// Whether a specific method is mutable.
+    pub fn is_mutable_method(method: &str) -> bool {
+        matches!(method, "push" | "pop" | "insert" | "remove")
+    }
+}
+
+/// The missing method error message.
+#[cold]
+fn missing_method(type_name: &str, method: &str) -> String {
+    format!("type {type_name} has no method `{method}`")
 }
 
 impl Default for Value {
diff --git a/src/geom/angle.rs b/src/geom/angle.rs
index b4d6f79a..b64ec77e 100644
--- a/src/geom/angle.rs
+++ b/src/geom/angle.rs
@@ -129,7 +129,7 @@ assign_impl!(Angle /= f64);
 
 impl Sum for Angle {
     fn sum<I: Iterator<Item = Angle>>(iter: I) -> Self {
-        iter.fold(Angle::zero(), Add::add)
+        Self(iter.map(|s| s.0).sum())
     }
 }
 /// Different units of angular measurement.
diff --git a/src/library/mod.rs b/src/library/mod.rs
index 087ff7ea..528a2ce7 100644
--- a/src/library/mod.rs
+++ b/src/library/mod.rs
@@ -67,13 +67,10 @@ pub fn new() -> Scope {
     std.def_node::<math::MathNode>("math");
 
     // Utility functions.
-    std.def_fn("assert", utility::assert);
     std.def_fn("type", utility::type_);
-    std.def_fn("repr", utility::repr);
-    std.def_fn("join", utility::join);
+    std.def_fn("assert", utility::assert);
     std.def_fn("int", utility::int);
     std.def_fn("float", utility::float);
-    std.def_fn("str", utility::str);
     std.def_fn("abs", utility::abs);
     std.def_fn("min", utility::min);
     std.def_fn("max", utility::max);
@@ -83,13 +80,13 @@ pub fn new() -> Scope {
     std.def_fn("range", utility::range);
     std.def_fn("rgb", utility::rgb);
     std.def_fn("cmyk", utility::cmyk);
+    std.def_fn("repr", utility::repr);
+    std.def_fn("str", utility::str);
     std.def_fn("lower", utility::lower);
     std.def_fn("upper", utility::upper);
     std.def_fn("letter", utility::letter);
     std.def_fn("roman", utility::roman);
     std.def_fn("symbol", utility::symbol);
-    std.def_fn("len", utility::len);
-    std.def_fn("sorted", utility::sorted);
 
     // Predefined colors.
     std.def_const("black", Color::BLACK);
diff --git a/src/library/utility/color.rs b/src/library/utility/color.rs
new file mode 100644
index 00000000..df24f615
--- /dev/null
+++ b/src/library/utility/color.rs
@@ -0,0 +1,58 @@
+use std::str::FromStr;
+
+use crate::library::prelude::*;
+
+/// Create an RGB(A) color.
+pub fn rgb(_: &mut Context, args: &mut Args) -> TypResult<Value> {
+    Ok(Value::from(
+        if let Some(string) = args.find::<Spanned<EcoString>>()? {
+            match RgbaColor::from_str(&string.v) {
+                Ok(color) => color,
+                Err(_) => bail!(string.span, "invalid hex string"),
+            }
+        } else {
+            struct Component(u8);
+
+            castable! {
+                Component,
+                Expected: "integer or relative",
+                Value::Int(v) => match v {
+                    0 ..= 255 => Self(v as u8),
+                    _ => Err("must be between 0 and 255")?,
+                },
+                Value::Relative(v) => if (0.0 ..= 1.0).contains(&v.get()) {
+                    Self((v.get() * 255.0).round() as u8)
+                } else {
+                    Err("must be between 0% and 100%")?
+                },
+            }
+
+            let Component(r) = args.expect("red component")?;
+            let Component(g) = args.expect("green component")?;
+            let Component(b) = args.expect("blue component")?;
+            let Component(a) = args.eat()?.unwrap_or(Component(255));
+            RgbaColor::new(r, g, b, a)
+        },
+    ))
+}
+
+/// Create a CMYK color.
+pub fn cmyk(_: &mut Context, args: &mut Args) -> TypResult<Value> {
+    struct Component(u8);
+
+    castable! {
+        Component,
+        Expected: "relative",
+        Value::Relative(v) => if (0.0 ..= 1.0).contains(&v.get()) {
+            Self((v.get() * 255.0).round() as u8)
+        } else {
+            Err("must be between 0% and 100%")?
+        },
+    }
+
+    let Component(c) = args.expect("cyan component")?;
+    let Component(m) = args.expect("magenta component")?;
+    let Component(y) = args.expect("yellow component")?;
+    let Component(k) = args.expect("key component")?;
+    Ok(Value::Color(CmykColor::new(c, m, y, k).into()))
+}
diff --git a/src/library/utility/math.rs b/src/library/utility/math.rs
index e48af426..0aebc573 100644
--- a/src/library/utility/math.rs
+++ b/src/library/utility/math.rs
@@ -2,6 +2,35 @@ use std::cmp::Ordering;
 
 use crate::library::prelude::*;
 
+/// Convert a value to a integer.
+pub fn int(_: &mut Context, args: &mut Args) -> TypResult<Value> {
+    let Spanned { v, span } = args.expect("value")?;
+    Ok(Value::Int(match v {
+        Value::Bool(v) => v as i64,
+        Value::Int(v) => v,
+        Value::Float(v) => v as i64,
+        Value::Str(v) => match v.parse() {
+            Ok(v) => v,
+            Err(_) => bail!(span, "invalid integer"),
+        },
+        v => bail!(span, "cannot convert {} to integer", v.type_name()),
+    }))
+}
+
+/// Convert a value to a float.
+pub fn float(_: &mut Context, args: &mut Args) -> TypResult<Value> {
+    let Spanned { v, span } = args.expect("value")?;
+    Ok(Value::Float(match v {
+        Value::Int(v) => v as f64,
+        Value::Float(v) => v,
+        Value::Str(v) => match v.parse() {
+            Ok(v) => v,
+            Err(_) => bail!(span, "invalid float"),
+        },
+        v => bail!(span, "cannot convert {} to float", v.type_name()),
+    }))
+}
+
 /// The absolute value of a numeric value.
 pub fn abs(_: &mut Context, args: &mut Args) -> TypResult<Value> {
     let Spanned { v, span } = args.expect("numeric value")?;
diff --git a/src/library/utility/mod.rs b/src/library/utility/mod.rs
index d85c3f12..13220242 100644
--- a/src/library/utility/mod.rs
+++ b/src/library/utility/mod.rs
@@ -1,15 +1,19 @@
 //! Computational utility functions.
 
+mod color;
 mod math;
-mod numbering;
+mod string;
 
+pub use color::*;
 pub use math::*;
-pub use numbering::*;
-
-use std::str::FromStr;
+pub use string::*;
 
 use crate::library::prelude::*;
-use crate::library::text::{Case, TextNode};
+
+/// The name of a value's type.
+pub fn type_(_: &mut Context, args: &mut Args) -> TypResult<Value> {
+    Ok(args.expect::<Value>("value")?.type_name().into())
+}
 
 /// Ensure that a condition is fulfilled.
 pub fn assert(_: &mut Context, args: &mut Args) -> TypResult<Value> {
@@ -19,169 +23,3 @@ pub fn assert(_: &mut Context, args: &mut Args) -> TypResult<Value> {
     }
     Ok(Value::None)
 }
-
-/// The name of a value's type.
-pub fn type_(_: &mut Context, args: &mut Args) -> TypResult<Value> {
-    Ok(args.expect::<Value>("value")?.type_name().into())
-}
-
-/// The string representation of a value.
-pub fn repr(_: &mut Context, args: &mut Args) -> TypResult<Value> {
-    Ok(args.expect::<Value>("value")?.repr().into())
-}
-
-/// Join a sequence of values, optionally interspersing it with another value.
-pub fn join(_: &mut Context, args: &mut Args) -> TypResult<Value> {
-    let span = args.span;
-    let sep = args.named::<Value>("sep")?.unwrap_or(Value::None);
-
-    let mut result = Value::None;
-    let mut iter = args.all::<Value>()?.into_iter();
-
-    if let Some(first) = iter.next() {
-        result = first;
-    }
-
-    for value in iter {
-        result = result.join(sep.clone()).at(span)?;
-        result = result.join(value).at(span)?;
-    }
-
-    Ok(result)
-}
-
-/// Convert a value to a integer.
-pub fn int(_: &mut Context, args: &mut Args) -> TypResult<Value> {
-    let Spanned { v, span } = args.expect("value")?;
-    Ok(Value::Int(match v {
-        Value::Bool(v) => v as i64,
-        Value::Int(v) => v,
-        Value::Float(v) => v as i64,
-        Value::Str(v) => match v.parse() {
-            Ok(v) => v,
-            Err(_) => bail!(span, "invalid integer"),
-        },
-        v => bail!(span, "cannot convert {} to integer", v.type_name()),
-    }))
-}
-
-/// Convert a value to a float.
-pub fn float(_: &mut Context, args: &mut Args) -> TypResult<Value> {
-    let Spanned { v, span } = args.expect("value")?;
-    Ok(Value::Float(match v {
-        Value::Int(v) => v as f64,
-        Value::Float(v) => v,
-        Value::Str(v) => match v.parse() {
-            Ok(v) => v,
-            Err(_) => bail!(span, "invalid float"),
-        },
-        v => bail!(span, "cannot convert {} to float", v.type_name()),
-    }))
-}
-
-/// Cconvert a value to a string.
-pub fn str(_: &mut Context, args: &mut Args) -> TypResult<Value> {
-    let Spanned { v, span } = args.expect("value")?;
-    Ok(Value::Str(match v {
-        Value::Int(v) => format_eco!("{}", v),
-        Value::Float(v) => format_eco!("{}", v),
-        Value::Str(v) => v,
-        v => bail!(span, "cannot convert {} to string", v.type_name()),
-    }))
-}
-
-/// Create an RGB(A) color.
-pub fn rgb(_: &mut Context, args: &mut Args) -> TypResult<Value> {
-    Ok(Value::from(
-        if let Some(string) = args.find::<Spanned<EcoString>>()? {
-            match RgbaColor::from_str(&string.v) {
-                Ok(color) => color,
-                Err(_) => bail!(string.span, "invalid hex string"),
-            }
-        } else {
-            struct Component(u8);
-
-            castable! {
-                Component,
-                Expected: "integer or relative",
-                Value::Int(v) => match v {
-                    0 ..= 255 => Self(v as u8),
-                    _ => Err("must be between 0 and 255")?,
-                },
-                Value::Relative(v) => if (0.0 ..= 1.0).contains(&v.get()) {
-                    Self((v.get() * 255.0).round() as u8)
-                } else {
-                    Err("must be between 0% and 100%")?
-                },
-            }
-
-            let Component(r) = args.expect("red component")?;
-            let Component(g) = args.expect("green component")?;
-            let Component(b) = args.expect("blue component")?;
-            let Component(a) = args.eat()?.unwrap_or(Component(255));
-            RgbaColor::new(r, g, b, a)
-        },
-    ))
-}
-
-/// Create a CMYK color.
-pub fn cmyk(_: &mut Context, args: &mut Args) -> TypResult<Value> {
-    struct Component(u8);
-
-    castable! {
-        Component,
-        Expected: "relative",
-        Value::Relative(v) => if (0.0 ..= 1.0).contains(&v.get()) {
-            Self((v.get() * 255.0).round() as u8)
-        } else {
-            Err("must be between 0% and 100%")?
-        },
-    }
-
-    let Component(c) = args.expect("cyan component")?;
-    let Component(m) = args.expect("magenta component")?;
-    let Component(y) = args.expect("yellow component")?;
-    let Component(k) = args.expect("key component")?;
-    Ok(Value::Color(CmykColor::new(c, m, y, k).into()))
-}
-
-/// The length of a string, an array or a dictionary.
-pub fn len(_: &mut Context, args: &mut Args) -> TypResult<Value> {
-    let Spanned { v, span } = args.expect("collection")?;
-    Ok(Value::Int(match v {
-        Value::Str(v) => v.len() as i64,
-        Value::Array(v) => v.len(),
-        Value::Dict(v) => v.len(),
-        v => bail!(
-            span,
-            "expected string, array or dictionary, found {}",
-            v.type_name(),
-        ),
-    }))
-}
-
-/// Convert a string to lowercase.
-pub fn lower(_: &mut Context, args: &mut Args) -> TypResult<Value> {
-    case(Case::Lower, args)
-}
-
-/// Convert a string to uppercase.
-pub fn upper(_: &mut Context, args: &mut Args) -> TypResult<Value> {
-    case(Case::Upper, args)
-}
-
-/// Change the case of a string or content.
-fn case(case: Case, args: &mut Args) -> TypResult<Value> {
-    let Spanned { v, span } = args.expect("string or content")?;
-    Ok(match v {
-        Value::Str(v) => Value::Str(case.apply(&v).into()),
-        Value::Content(v) => Value::Content(v.styled(TextNode::CASE, Some(case))),
-        v => bail!(span, "expected string or content, found {}", v.type_name()),
-    })
-}
-
-/// The sorted version of an array.
-pub fn sorted(_: &mut Context, args: &mut Args) -> TypResult<Value> {
-    let Spanned { v, span } = args.expect::<Spanned<Array>>("array")?;
-    Ok(Value::Array(v.sorted().at(span)?))
-}
diff --git a/src/library/utility/numbering.rs b/src/library/utility/string.rs
index 0070873f..92d80be2 100644
--- a/src/library/utility/numbering.rs
+++ b/src/library/utility/string.rs
@@ -1,4 +1,41 @@
 use crate::library::prelude::*;
+use crate::library::text::{Case, TextNode};
+
+/// The string representation of a value.
+pub fn repr(_: &mut Context, args: &mut Args) -> TypResult<Value> {
+    Ok(args.expect::<Value>("value")?.repr().into())
+}
+
+/// Cconvert a value to a string.
+pub fn str(_: &mut Context, args: &mut Args) -> TypResult<Value> {
+    let Spanned { v, span } = args.expect("value")?;
+    Ok(Value::Str(match v {
+        Value::Int(v) => format_eco!("{}", v),
+        Value::Float(v) => format_eco!("{}", v),
+        Value::Str(v) => v,
+        v => bail!(span, "cannot convert {} to string", v.type_name()),
+    }))
+}
+
+/// Convert a string to lowercase.
+pub fn lower(_: &mut Context, args: &mut Args) -> TypResult<Value> {
+    case(Case::Lower, args)
+}
+
+/// Convert a string to uppercase.
+pub fn upper(_: &mut Context, args: &mut Args) -> TypResult<Value> {
+    case(Case::Upper, args)
+}
+
+/// Change the case of a string or content.
+fn case(case: Case, args: &mut Args) -> TypResult<Value> {
+    let Spanned { v, span } = args.expect("string or content")?;
+    Ok(match v {
+        Value::Str(v) => Value::Str(case.apply(&v).into()),
+        Value::Content(v) => Value::Content(v.styled(TextNode::CASE, Some(case))),
+        v => bail!(span, "expected string or content, found {}", v.type_name()),
+    })
+}
 
 /// Converts an integer into one or multiple letters.
 pub fn letter(_: &mut Context, args: &mut Args) -> TypResult<Value> {
diff --git a/src/parse/incremental.rs b/src/parse/incremental.rs
index 468f344e..a2ba502b 100644
--- a/src/parse/incremental.rs
+++ b/src/parse/incremental.rs
@@ -4,7 +4,8 @@ use std::sync::Arc;
 use crate::syntax::{Green, GreenNode, NodeKind};
 
 use super::{
-    is_newline, parse, reparse_block, reparse_content, reparse_markup_elements, TokenMode,
+    is_newline, parse, reparse_code_block, reparse_content_block,
+    reparse_markup_elements, TokenMode,
 };
 
 /// Allows partial refreshs of the [`Green`] node tree.
@@ -210,12 +211,12 @@ impl Reparser<'_> {
         }
 
         let (newborns, terminated, amount) = match mode {
-            ReparseMode::Code => reparse_block(
+            ReparseMode::Code => reparse_code_block(
                 &prefix,
                 &self.src[newborn_span.start ..],
                 newborn_span.len(),
             ),
-            ReparseMode::Content => reparse_content(
+            ReparseMode::Content => reparse_content_block(
                 &prefix,
                 &self.src[newborn_span.start ..],
                 newborn_span.len(),
@@ -344,7 +345,6 @@ mod tests {
         test("this~is -- in my opinion -- spectacular", 8 .. 10, "---", 5 .. 25);
         test("understanding `code` is complicated", 15 .. 15, "C ", 14 .. 22);
         test("{ let x = g() }", 10 .. 12, "f(54", 0 .. 17);
-        test("a #let rect with (fill: eastern)\nb", 16 .. 31, " (stroke: conifer", 2 .. 34);
         test(r#"a ```typst hello``` b"#, 16 .. 17, "", 2 .. 18);
         test(r#"a ```typst hello```"#, 16 .. 17, "", 2 .. 18);
         test("#for", 4 .. 4, "//", 0 .. 6);
diff --git a/src/parse/mod.rs b/src/parse/mod.rs
index 5eaba8b0..58b81521 100644
--- a/src/parse/mod.rs
+++ b/src/parse/mod.rs
@@ -31,7 +31,7 @@ pub fn parse(src: &str) -> Arc<GreenNode> {
 /// Reparse a code block.
 ///
 /// Returns `Some` if all of the input was consumed.
-pub fn reparse_block(
+pub fn reparse_code_block(
     prefix: &str,
     src: &str,
     end_pos: usize,
@@ -41,7 +41,7 @@ pub fn reparse_block(
         return None;
     }
 
-    block(&mut p);
+    code_block(&mut p);
 
     let (mut green, terminated) = p.consume()?;
     let first = green.remove(0);
@@ -55,7 +55,7 @@ pub fn reparse_block(
 /// Reparse a content block.
 ///
 /// Returns `Some` if all of the input was consumed.
-pub fn reparse_content(
+pub fn reparse_content_block(
     prefix: &str,
     src: &str,
     end_pos: usize,
@@ -65,7 +65,7 @@ pub fn reparse_content(
         return None;
     }
 
-    content(&mut p);
+    content_block(&mut p);
 
     let (mut green, terminated) = p.consume()?;
     let first = green.remove(0);
@@ -236,8 +236,8 @@ fn markup_node(p: &mut Parser, at_start: &mut bool) {
         | NodeKind::Include => markup_expr(p),
 
         // Code and content block.
-        NodeKind::LeftBrace => block(p),
-        NodeKind::LeftBracket => content(p),
+        NodeKind::LeftBrace => code_block(p),
+        NodeKind::LeftBracket => content_block(p),
 
         NodeKind::Error(_, _) => p.eat(),
         _ => p.unexpected(),
@@ -364,7 +364,7 @@ fn expr_prec(p: &mut Parser, atomic: bool, min_prec: usize) -> ParseResult {
         // Exclamation mark, parenthesis or bracket means this is a function
         // call.
         if let Some(NodeKind::LeftParen | NodeKind::LeftBracket) = p.peek_direct() {
-            call(p, marker)?;
+            func_call(p, marker)?;
             continue;
         }
 
@@ -372,8 +372,9 @@ fn expr_prec(p: &mut Parser, atomic: bool, min_prec: usize) -> ParseResult {
             break;
         }
 
-        if p.at(&NodeKind::With) {
-            with_expr(p, marker)?;
+        if p.at(&NodeKind::Dot) {
+            method_call(p, marker)?;
+            continue;
         }
 
         let op = if p.eat_if(&NodeKind::Not) {
@@ -432,8 +433,8 @@ fn primary(p: &mut Parser, atomic: bool) -> ParseResult {
 
         // Structures.
         Some(NodeKind::LeftParen) => parenthesized(p, atomic),
-        Some(NodeKind::LeftBrace) => Ok(block(p)),
-        Some(NodeKind::LeftBracket) => Ok(content(p)),
+        Some(NodeKind::LeftBrace) => Ok(code_block(p)),
+        Some(NodeKind::LeftBracket) => Ok(content_block(p)),
 
         // Keywords.
         Some(NodeKind::Let) => let_expr(p),
@@ -671,7 +672,7 @@ fn params(p: &mut Parser, marker: Marker) {
 }
 
 /// Parse a code block: `{...}`.
-fn block(p: &mut Parser) {
+fn code_block(p: &mut Parser) {
     p.perform(NodeKind::CodeBlock, |p| {
         p.start_group(Group::Brace);
         while !p.eof() {
@@ -689,7 +690,7 @@ fn block(p: &mut Parser) {
 }
 
 // Parse a content block: `[...]`.
-fn content(p: &mut Parser) {
+fn content_block(p: &mut Parser) {
     p.perform(NodeKind::ContentBlock, |p| {
         p.start_group(Group::Bracket);
         markup(p, true);
@@ -698,8 +699,17 @@ fn content(p: &mut Parser) {
 }
 
 /// Parse a function call.
-fn call(p: &mut Parser, callee: Marker) -> ParseResult {
-    callee.perform(p, NodeKind::CallExpr, |p| args(p, true, true))
+fn func_call(p: &mut Parser, callee: Marker) -> ParseResult {
+    callee.perform(p, NodeKind::FuncCall, |p| args(p, true, true))
+}
+
+/// Parse a method call.
+fn method_call(p: &mut Parser, marker: Marker) -> ParseResult {
+    marker.perform(p, NodeKind::MethodCall, |p| {
+        p.eat_assert(&NodeKind::Dot);
+        ident(p)?;
+        args(p, true, true)
+    })
 }
 
 /// Parse the arguments to a function call.
@@ -721,21 +731,13 @@ fn args(p: &mut Parser, direct: bool, brackets: bool) -> ParseResult {
         }
 
         while brackets && p.peek_direct() == Some(&NodeKind::LeftBracket) {
-            content(p);
+            content_block(p);
         }
     });
 
     Ok(())
 }
 
-/// Parse a with expression.
-fn with_expr(p: &mut Parser, marker: Marker) -> ParseResult {
-    marker.perform(p, NodeKind::WithExpr, |p| {
-        p.eat_assert(&NodeKind::With);
-        args(p, false, false)
-    })
-}
-
 /// Parse a let expression.
 fn let_expr(p: &mut Parser) -> ParseResult {
     p.perform(NodeKind::LetExpr, |p| {
@@ -744,30 +746,26 @@ fn let_expr(p: &mut Parser) -> ParseResult {
         let marker = p.marker();
         ident(p)?;
 
-        if p.at(&NodeKind::With) {
-            with_expr(p, marker)?;
-        } else {
-            // If a parenthesis follows, this is a function definition.
-            let has_params = p.peek_direct() == Some(&NodeKind::LeftParen);
-            if has_params {
-                let marker = p.marker();
-                p.start_group(Group::Paren);
-                collection(p);
-                p.end_group();
-                params(p, marker);
-            }
+        // If a parenthesis follows, this is a function definition.
+        let has_params = p.peek_direct() == Some(&NodeKind::LeftParen);
+        if has_params {
+            let marker = p.marker();
+            p.start_group(Group::Paren);
+            collection(p);
+            p.end_group();
+            params(p, marker);
+        }
 
-            if p.eat_if(&NodeKind::Eq) {
-                expr(p)?;
-            } else if has_params {
-                // Function definitions must have a body.
-                p.expected("body");
-            }
+        if p.eat_if(&NodeKind::Eq) {
+            expr(p)?;
+        } else if has_params {
+            // Function definitions must have a body.
+            p.expected("body");
+        }
 
-            // Rewrite into a closure expression if it's a function definition.
-            if has_params {
-                marker.end(p, NodeKind::ClosureExpr);
-            }
+        // Rewrite into a closure expression if it's a function definition.
+        if has_params {
+            marker.end(p, NodeKind::ClosureExpr);
         }
 
         Ok(())
@@ -931,8 +929,8 @@ fn return_expr(p: &mut Parser) -> ParseResult {
 /// Parse a control flow body.
 fn body(p: &mut Parser) -> ParseResult {
     match p.peek() {
-        Some(NodeKind::LeftBracket) => Ok(content(p)),
-        Some(NodeKind::LeftBrace) => Ok(block(p)),
+        Some(NodeKind::LeftBracket) => Ok(content_block(p)),
+        Some(NodeKind::LeftBrace) => Ok(code_block(p)),
         _ => {
             p.expected("body");
             Err(ParseError)
diff --git a/src/parse/parser.rs b/src/parse/parser.rs
index 33cf489c..63ba4918 100644
--- a/src/parse/parser.rs
+++ b/src/parse/parser.rs
@@ -352,7 +352,16 @@ impl<'s> Parser<'s> {
 
         match self.groups.last().map(|group| group.kind) {
             Some(Group::Strong | Group::Emph) => n >= 2,
-            Some(Group::Expr | Group::Imports) => n >= 1,
+            Some(Group::Imports) => n >= 1,
+            Some(Group::Expr) if n >= 1 => {
+                // Allow else and method call to continue on next line.
+                self.groups.iter().nth_back(1).map(|group| group.kind)
+                    != Some(Group::Brace)
+                    || !matches!(
+                        self.tokens.clone().next(),
+                        Some(NodeKind::Else | NodeKind::Dot)
+                    )
+            }
             _ => false,
         }
     }
diff --git a/src/parse/tokens.rs b/src/parse/tokens.rs
index 752714fd..0c05d770 100644
--- a/src/parse/tokens.rs
+++ b/src/parse/tokens.rs
@@ -10,6 +10,7 @@ use crate::syntax::{ErrorPos, NodeKind};
 use crate::util::EcoString;
 
 /// An iterator over the tokens of a string of source code.
+#[derive(Clone)]
 pub struct Tokens<'s> {
     /// The underlying scanner.
     s: Scanner<'s>,
@@ -184,6 +185,7 @@ impl<'s> Tokens<'s> {
             '=' => NodeKind::Eq,
             '<' => NodeKind::Lt,
             '>' => NodeKind::Gt,
+            '.' if self.s.check_or(true, |n| !n.is_ascii_digit()) => NodeKind::Dot,
 
             // Identifiers.
             c if is_id_start(c) => self.ident(start),
@@ -572,7 +574,6 @@ fn keyword(ident: &str) -> Option<NodeKind> {
         "not" => NodeKind::Not,
         "and" => NodeKind::And,
         "or" => NodeKind::Or,
-        "with" => NodeKind::With,
         "let" => NodeKind::Let,
         "set" => NodeKind::Set,
         "show" => NodeKind::Show,
@@ -859,6 +860,7 @@ mod tests {
         t!(Code: "-"        => Minus);
         t!(Code[" a1"]: "*" => Star);
         t!(Code[" a1"]: "/" => Slash);
+        t!(Code[" a/"]: "." => Dot);
         t!(Code: "="        => Eq);
         t!(Code: "=="       => EqEq);
         t!(Code: "!="       => ExclEq);
@@ -875,7 +877,7 @@ mod tests {
 
         // Test combinations.
         t!(Code: "<=>"        => LtEq, Gt);
-        t!(Code[" a/"]: "..." => Dots, Invalid("."));
+        t!(Code[" a/"]: "..." => Dots, Dot);
 
         // Test hyphen as symbol vs part of identifier.
         t!(Code[" /"]: "-1"   => Minus, Int(1));
diff --git a/src/syntax/ast.rs b/src/syntax/ast.rs
index b8780590..cb0a99b9 100644
--- a/src/syntax/ast.rs
+++ b/src/syntax/ast.rs
@@ -234,11 +234,11 @@ pub enum Expr {
     /// A binary operation: `a + b`.
     Binary(BinaryExpr),
     /// An invocation of a function: `f(x, y)`.
-    Call(CallExpr),
+    FuncCall(FuncCall),
+    /// An invocation of a method: `array.push(v)`.
+    MethodCall(MethodCall),
     /// A closure expression: `(x, y) => z`.
     Closure(ClosureExpr),
-    /// A with expression: `f with (x, y: 1)`.
-    With(WithExpr),
     /// A let expression: `let x = 1`.
     Let(LetExpr),
     /// A set expression: `set text(...)`.
@@ -276,9 +276,9 @@ impl TypedNode for Expr {
             NodeKind::DictExpr => node.cast().map(Self::Dict),
             NodeKind::UnaryExpr => node.cast().map(Self::Unary),
             NodeKind::BinaryExpr => node.cast().map(Self::Binary),
-            NodeKind::CallExpr => node.cast().map(Self::Call),
+            NodeKind::FuncCall => node.cast().map(Self::FuncCall),
+            NodeKind::MethodCall => node.cast().map(Self::MethodCall),
             NodeKind::ClosureExpr => node.cast().map(Self::Closure),
-            NodeKind::WithExpr => node.cast().map(Self::With),
             NodeKind::LetExpr => node.cast().map(Self::Let),
             NodeKind::SetExpr => node.cast().map(Self::Set),
             NodeKind::ShowExpr => node.cast().map(Self::Show),
@@ -306,9 +306,9 @@ impl TypedNode for Expr {
             Self::Group(v) => v.as_red(),
             Self::Unary(v) => v.as_red(),
             Self::Binary(v) => v.as_red(),
-            Self::Call(v) => v.as_red(),
+            Self::FuncCall(v) => v.as_red(),
+            Self::MethodCall(v) => v.as_red(),
             Self::Closure(v) => v.as_red(),
-            Self::With(v) => v.as_red(),
             Self::Let(v) => v.as_red(),
             Self::Set(v) => v.as_red(),
             Self::Show(v) => v.as_red(),
@@ -331,7 +331,7 @@ impl Expr {
         matches!(
             self,
             Self::Ident(_)
-                | Self::Call(_)
+                | Self::FuncCall(_)
                 | Self::Let(_)
                 | Self::Set(_)
                 | Self::Show(_)
@@ -735,19 +735,45 @@ pub enum Associativity {
 }
 
 node! {
-    /// An invocation of a function: `foo(...)`.
-    CallExpr: CallExpr
+    /// An invocation of a function: `f(x, y)`.
+    FuncCall: FuncCall
 }
 
-impl CallExpr {
+impl FuncCall {
     /// The function to call.
     pub fn callee(&self) -> Expr {
-        self.0.cast_first_child().expect("call is missing callee")
+        self.0.cast_first_child().expect("function call is missing callee")
     }
 
     /// The arguments to the function.
     pub fn args(&self) -> CallArgs {
-        self.0.cast_last_child().expect("call is missing argument list")
+        self.0
+            .cast_last_child()
+            .expect("function call is missing argument list")
+    }
+}
+
+node! {
+    /// An invocation of a method: `array.push(v)`.
+    MethodCall: MethodCall
+}
+
+impl MethodCall {
+    /// The value to call the method on.
+    pub fn receiver(&self) -> Expr {
+        self.0.cast_first_child().expect("method call is missing callee")
+    }
+
+    /// The name of the method.
+    pub fn method(&self) -> Ident {
+        self.0.cast_last_child().expect("method call is missing name")
+    }
+
+    /// The arguments to the method.
+    pub fn args(&self) -> CallArgs {
+        self.0
+            .cast_last_child()
+            .expect("method call is missing argument list")
     }
 }
 
@@ -863,25 +889,6 @@ impl TypedNode for ClosureParam {
 }
 
 node! {
-    /// A with expression: `f with (x, y: 1)`.
-    WithExpr
-}
-
-impl WithExpr {
-    /// The function to apply the arguments to.
-    pub fn callee(&self) -> Expr {
-        self.0.cast_first_child().expect("with expression is missing callee")
-    }
-
-    /// The arguments to apply to the function.
-    pub fn args(&self) -> CallArgs {
-        self.0
-            .cast_first_child()
-            .expect("with expression is missing argument list")
-    }
-}
-
-node! {
     /// A let expression: `let x = 1`.
     LetExpr
 }
@@ -891,10 +898,6 @@ impl LetExpr {
     pub fn binding(&self) -> Ident {
         match self.0.cast_first_child() {
             Some(Expr::Ident(binding)) => binding,
-            Some(Expr::With(with)) => match with.callee() {
-                Expr::Ident(binding) => binding,
-                _ => panic!("let .. with callee must be identifier"),
-            },
             Some(Expr::Closure(closure)) => {
                 closure.name().expect("let-bound closure is missing name")
             }
diff --git a/src/syntax/highlight.rs b/src/syntax/highlight.rs
index c0e3376e..bad434b9 100644
--- a/src/syntax/highlight.rs
+++ b/src/syntax/highlight.rs
@@ -11,10 +11,10 @@ pub fn highlight<F>(node: RedRef, range: Range<usize>, f: &mut F)
 where
     F: FnMut(Range<usize>, Category),
 {
-    for child in node.children() {
+    for (i, child) in node.children().enumerate() {
         let span = child.span();
         if range.start <= span.end && range.end >= span.start {
-            if let Some(category) = Category::determine(child, node) {
+            if let Some(category) = Category::determine(child, node, i) {
                 f(span.to_range(), category);
             }
             highlight(child, range.clone(), f);
@@ -44,9 +44,9 @@ fn highlight_syntect_impl<F>(
         return;
     }
 
-    for child in node.children() {
+    for (i, child) in node.children().enumerate() {
         let mut scopes = scopes.clone();
-        if let Some(category) = Category::determine(child, node) {
+        if let Some(category) = Category::determine(child, node, i) {
             scopes.push(Scope::new(category.tm_scope()).unwrap())
         }
         highlight_syntect_impl(child, scopes, highlighter, f);
@@ -101,8 +101,9 @@ pub enum Category {
 }
 
 impl Category {
-    /// Determine the highlighting category of a node given its parent.
-    pub fn determine(child: RedRef, parent: RedRef) -> Option<Category> {
+    /// Determine the highlighting category of a node given its parent and its
+    /// index in its siblings.
+    pub fn determine(child: RedRef, parent: RedRef, i: usize) -> Option<Category> {
         match child.kind() {
             NodeKind::LeftBrace => Some(Category::Bracket),
             NodeKind::RightBrace => Some(Category::Bracket),
@@ -133,7 +134,6 @@ impl Category {
             NodeKind::Not => Some(Category::Keyword),
             NodeKind::And => Some(Category::Keyword),
             NodeKind::Or => Some(Category::Keyword),
-            NodeKind::With => Some(Category::Keyword),
             NodeKind::Let => Some(Category::Keyword),
             NodeKind::Set => Some(Category::Keyword),
             NodeKind::Show => Some(Category::Keyword),
@@ -156,6 +156,7 @@ impl Category {
                 _ => Some(Category::Operator),
             },
             NodeKind::Slash => Some(Category::Operator),
+            NodeKind::Dot => Some(Category::Operator),
             NodeKind::PlusEq => Some(Category::Operator),
             NodeKind::HyphEq => Some(Category::Operator),
             NodeKind::StarEq => Some(Category::Operator),
@@ -176,13 +177,11 @@ impl Category {
             NodeKind::Auto => Some(Category::Auto),
             NodeKind::Ident(_) => match parent.kind() {
                 NodeKind::Named => None,
-                NodeKind::ClosureExpr if child.span().start == parent.span().start => {
-                    Some(Category::Function)
-                }
-                NodeKind::WithExpr => Some(Category::Function),
+                NodeKind::ClosureExpr if i == 0 => Some(Category::Function),
                 NodeKind::SetExpr => Some(Category::Function),
                 NodeKind::ShowExpr => Some(Category::Function),
-                NodeKind::CallExpr => Some(Category::Function),
+                NodeKind::FuncCall => Some(Category::Function),
+                NodeKind::MethodCall if i > 0 => Some(Category::Function),
                 _ => Some(Category::Variable),
             },
             NodeKind::Bool(_) => Some(Category::Bool),
@@ -210,12 +209,12 @@ impl Category {
             NodeKind::Named => None,
             NodeKind::UnaryExpr => None,
             NodeKind::BinaryExpr => None,
-            NodeKind::CallExpr => None,
+            NodeKind::FuncCall => None,
+            NodeKind::MethodCall => None,
             NodeKind::CallArgs => None,
             NodeKind::Spread => None,
             NodeKind::ClosureExpr => None,
             NodeKind::ClosureParams => None,
-            NodeKind::WithExpr => None,
             NodeKind::LetExpr => None,
             NodeKind::SetExpr => None,
             NodeKind::ShowExpr => None,
diff --git a/src/syntax/mod.rs b/src/syntax/mod.rs
index e15cfabc..d0920d20 100644
--- a/src/syntax/mod.rs
+++ b/src/syntax/mod.rs
@@ -509,6 +509,8 @@ pub enum NodeKind {
     Minus,
     /// A slash: `/`.
     Slash,
+    /// A dot: `.`.
+    Dot,
     /// A single equals sign: `=`.
     Eq,
     /// Two equals signs: `==`.
@@ -537,8 +539,6 @@ pub enum NodeKind {
     And,
     /// The `or` operator.
     Or,
-    /// The `with` operator.
-    With,
     /// Two dots: `..`.
     Dots,
     /// An equals sign followed by a greater-than sign: `=>`.
@@ -659,7 +659,9 @@ pub enum NodeKind {
     /// A binary operation: `a + b`.
     BinaryExpr,
     /// An invocation of a function: `f(x, y)`.
-    CallExpr,
+    FuncCall,
+    /// An invocation of a method: `array.push(v)`.
+    MethodCall,
     /// A function call's argument list: `(x, y)`.
     CallArgs,
     /// Spreaded arguments or a parameter sink: `..x`.
@@ -668,8 +670,6 @@ pub enum NodeKind {
     ClosureExpr,
     /// A closure's parameters: `(x, y)`.
     ClosureParams,
-    /// A with expression: `f with (x, y: 1)`.
-    WithExpr,
     /// A let expression: `let x = 1`.
     LetExpr,
     /// A set expression: `set text(...)`.
@@ -802,7 +802,7 @@ impl NodeKind {
             | Self::WhileExpr
             | Self::ForExpr
             | Self::ImportExpr
-            | Self::CallExpr
+            | Self::FuncCall
             | Self::IncludeExpr
             | Self::LineComment
             | Self::BlockComment
@@ -830,6 +830,7 @@ impl NodeKind {
             Self::Plus => "plus",
             Self::Minus => "minus",
             Self::Slash => "slash",
+            Self::Dot => "dot",
             Self::Eq => "assignment operator",
             Self::EqEq => "equality operator",
             Self::ExclEq => "inequality operator",
@@ -844,7 +845,6 @@ impl NodeKind {
             Self::Not => "operator `not`",
             Self::And => "operator `and`",
             Self::Or => "operator `or`",
-            Self::With => "operator `with`",
             Self::Dots => "dots",
             Self::Arrow => "arrow",
             Self::None => "`none`",
@@ -899,12 +899,12 @@ impl NodeKind {
             Self::Named => "named argument",
             Self::UnaryExpr => "unary expression",
             Self::BinaryExpr => "binary expression",
-            Self::CallExpr => "call",
+            Self::FuncCall => "function call",
+            Self::MethodCall => "method call",
             Self::CallArgs => "call arguments",
             Self::Spread => "parameter sink",
             Self::ClosureExpr => "closure",
             Self::ClosureParams => "closure parameters",
-            Self::WithExpr => "`with` expression",
             Self::LetExpr => "`let` expression",
             Self::SetExpr => "`set` expression",
             Self::ShowExpr => "`show` expression",
@@ -954,6 +954,7 @@ impl Hash for NodeKind {
             Self::Plus => {}
             Self::Minus => {}
             Self::Slash => {}
+            Self::Dot => {}
             Self::Eq => {}
             Self::EqEq => {}
             Self::ExclEq => {}
@@ -968,7 +969,6 @@ impl Hash for NodeKind {
             Self::Not => {}
             Self::And => {}
             Self::Or => {}
-            Self::With => {}
             Self::Dots => {}
             Self::Arrow => {}
             Self::None => {}
@@ -1023,12 +1023,12 @@ impl Hash for NodeKind {
             Self::Named => {}
             Self::UnaryExpr => {}
             Self::BinaryExpr => {}
-            Self::CallExpr => {}
+            Self::FuncCall => {}
+            Self::MethodCall => {}
             Self::CallArgs => {}
             Self::Spread => {}
             Self::ClosureExpr => {}
             Self::ClosureParams => {}
-            Self::WithExpr => {}
             Self::LetExpr => {}
             Self::SetExpr => {}
             Self::ShowExpr => {}
diff --git a/tests/ref/code/for.png b/tests/ref/code/for.png
index f9d42124..60c505ec 100644
--- a/tests/ref/code/for.png
+++ b/tests/ref/code/for.png
diff --git a/tests/ref/utility/basics.png b/tests/ref/utility/basics.png
deleted file mode 100644
index a80afe5f..00000000
--- a/tests/ref/utility/basics.png
+++ /dev/null
diff --git a/tests/ref/utility/collection.png b/tests/ref/utility/collection.png
new file mode 100644
index 00000000..e93e2beb
--- /dev/null
+++ b/tests/ref/utility/collection.png
diff --git a/tests/ref/utility/string.png b/tests/ref/utility/string.png
new file mode 100644
index 00000000..67563668
--- /dev/null
+++ b/tests/ref/utility/string.png
diff --git a/tests/typ/code/for.typ b/tests/typ/code/for.typ
index e161ba84..822f7423 100644
--- a/tests/typ/code/for.typ
+++ b/tests/typ/code/for.typ
@@ -32,10 +32,10 @@
 // Should output `2345`.
 #for v in (1, 2, 3, 4, 5, 6, 7) [#if v >= 2 and v <= 5 { repr(v) }]
 
-// Loop over captured arguments.
-#let f1(..args) = for v in args { (repr(v),) }
-#let f2(..args) = for k, v in args { (repr(k) + ": " + repr(v),) }
-#let f(..args) = join(sep: ", ", ..f1(..args), ..f2(..args))
+// Map captured arguments.
+#let f1(..args) = args.positional().map(repr)
+#let f2(..args) = args.named().pairs((k, v) => repr(k) + ": " + repr(v))
+#let f(..args) = (f1(..args) + f2(..args)).join(", ")
 #f(1, a: 2)
 
 ---
diff --git a/tests/typ/code/if.typ b/tests/typ/code/if.typ
index 0ab5c495..0d87c689 100644
--- a/tests/typ/code/if.typ
+++ b/tests/typ/code/if.typ
@@ -60,10 +60,10 @@
 
 #let nth(n) = {
   str(n)
-  (if n == 1 { "st" }
-   else if n == 2 { "nd" }
-   else if n == 3 { "rd" }
-   else { "th" })
+  if n == 1 { "st" }
+  else if n == 2 { "nd" }
+  else if n == 3 { "rd" }
+  else { "th" }
 }
 
 #test(nth(1), "1st")
diff --git a/tests/typ/code/methods.typ b/tests/typ/code/methods.typ
new file mode 100644
index 00000000..b5eff78d
--- /dev/null
+++ b/tests/typ/code/methods.typ
@@ -0,0 +1,50 @@
+// Test method calls.
+// Ref: false
+
+---
+// Test whitespace around dot.
+#test( "Hi there" . split() , ("Hi", "there"))
+
+---
+// Test mutating indexed value.
+{
+  let matrix = (((1,), (2,)), ((3,), (4,)))
+  matrix(1)(0).push(5)
+  test(matrix, (((1,), (2,)), ((3, 5), (4,))))
+}
+
+---
+// Test multiline chain in code block.
+{
+  let rewritten = "Hello. This is a sentence. And one more."
+    .split(".")
+    .map(s => s.trim())
+    .filter(s => s != "")
+    .map(s => s + "!")
+    .join([\ ])
+
+  test(rewritten, [Hello!\ This is a sentence!\ And one more!])
+}
+
+---
+// Error: 2:3-2:16 type array has no method `fun`
+#let numbers = ()
+{ numbers.fun() }
+
+---
+// Error: 2:3-2:44 cannot mutate a temporary value
+#let numbers = (1, 2, 3)
+{ numbers.map(v => v / 2).sorted().map(str).remove(4) }
+
+---
+// Error: 2:3-2:19 cannot mutate a temporary value
+#let numbers = (1, 2, 3)
+{ numbers.sorted() = 1 }
+
+---
+// Error: 3-6 cannot mutate a constant
+{ box = 1 }
+
+---
+// Error: 3-6 cannot mutate a constant
+{ box.push(1) }
diff --git a/tests/typ/code/ops-invalid.typ b/tests/typ/code/ops-invalid.typ
index 184e20cf..68bce4af 100644
--- a/tests/typ/code/ops-invalid.typ
+++ b/tests/typ/code/ops-invalid.typ
@@ -65,19 +65,11 @@
 { let x = 1; x += "2" }
 
 ---
-// Error: 13-14 expected argument list, found integer
-{ test with 2 }
-
----
-// Error: 3-4 expected function, found integer
-{ 1 with () }
-
----
-// Error: 3-6 cannot access this expression mutably
+// Error: 3-6 cannot mutate a temporary value
 { (x) = "" }
 
 ---
-// Error: 3-8 cannot access this expression mutably
+// Error: 3-8 cannot mutate a temporary value
 { 1 + 2 += 3 }
 
 ---
diff --git a/tests/typ/code/ops-prec.typ b/tests/typ/code/ops-prec.typ
index 2cec0d04..23afcc5f 100644
--- a/tests/typ/code/ops-prec.typ
+++ b/tests/typ/code/ops-prec.typ
@@ -13,7 +13,7 @@
 #test(not "b" == "b", false)
 
 // Assignment binds stronger than boolean operations.
-// Error: 2-7 cannot access this expression mutably
+// Error: 2-7 cannot mutate a temporary value
 {not x = "a"}
 
 ---
diff --git a/tests/typ/code/ops.typ b/tests/typ/code/ops.typ
index 899ee71c..79743f5d 100644
--- a/tests/typ/code/ops.typ
+++ b/tests/typ/code/ops.typ
@@ -184,21 +184,19 @@
 {"a" not}
 
 ---
-// Test `with` operator.
+// Test `with` method.
 
 // Apply positional arguments.
 #let add(x, y) = x + y
-#test((add with (2))(4), 6)
-
-// Let .. with .. syntax.
-#let f = add
-#let f with (2)
-#test(f(4), 6)
+#test(add.with(2)(3), 5)
+#test(add.with(2).with(3)(), 5)
+#test((add.with(2))(4), 6)
+#test((add.with(2).with(3))(), 5)
 
 // Make sure that named arguments are overridable.
 #let inc(x, y: 1) = x + y
 #test(inc(1), 2)
 
-#let inc with (y: 2)
-#test(inc(2), 4)
-#test(inc(2, y: 4), 6)
+#let inc2 = inc.with(y: 2)
+#test(inc2(2), 4)
+#test(inc2(2, y: 4), 6)
diff --git a/tests/typ/code/target.typ b/tests/typ/code/target.typ
index 73516817..6c321592 100644
--- a/tests/typ/code/target.typ
+++ b/tests/typ/code/target.typ
@@ -7,6 +7,6 @@
 #let d = 3
 #let value = [hi]
 #let item(a, b) = a + b
-#let fn = rect with (fill: conifer, padding: 5pt)
+#let fn = rect.with(fill: conifer, padding: 5pt)
 
 Some _includable_ text.
diff --git a/tests/typ/graphics/line.typ b/tests/typ/graphics/line.typ
index 452e52f3..050ce05c 100644
--- a/tests/typ/graphics/line.typ
+++ b/tests/typ/graphics/line.typ
@@ -34,10 +34,10 @@
     #line(length: +30%, origin: (25.4%, 48%), angle: -36deg)
     #line(length: +30%, origin: (25.6%, 48%), angle: -72deg)
     #line(length: +32%, origin: (8.50%, 02%), angle: 34deg)
-    ]
+  ]
 ]
 
-#align(center, grid(columns: (1fr, ) * 3, ..((star(20pt, thickness: .5pt), ) * 9)))
+#align(center, grid(columns: (1fr,) * 3, ..((star(20pt, thickness: .5pt),) * 9)))
 
 ---
 // Test errors.
diff --git a/tests/typ/graphics/shape-fill-stroke.typ b/tests/typ/graphics/shape-fill-stroke.typ
index 935f3bc7..dd5b9ee8 100644
--- a/tests/typ/graphics/shape-fill-stroke.typ
+++ b/tests/typ/graphics/shape-fill-stroke.typ
@@ -1,22 +1,22 @@
 // Test shape fill & stroke.
 
 ---
-#let rect with (width: 20pt, height: 10pt)
-#let items = for i, rect in (
-  rect(stroke: none),
-  rect(),
-  rect(fill: none),
-  rect(thickness: 2pt),
-  rect(stroke: eastern),
-  rect(stroke: eastern, thickness: 2pt),
-  rect(fill: eastern),
-  rect(fill: eastern, stroke: none),
-  rect(fill: forest, stroke: none, thickness: 2pt),
-  rect(fill: forest, stroke: conifer),
-  rect(fill: forest, stroke: black, thickness: 2pt),
-  rect(fill: forest, stroke: conifer, thickness: 2pt),
+#let variant = rect.with(width: 20pt, height: 10pt)
+#let items = for i, item in (
+  variant(stroke: none),
+  variant(),
+  variant(fill: none),
+  variant(thickness: 2pt),
+  variant(stroke: eastern),
+  variant(stroke: eastern, thickness: 2pt),
+  variant(fill: eastern),
+  variant(fill: eastern, stroke: none),
+  variant(fill: forest, stroke: none, thickness: 2pt),
+  variant(fill: forest, stroke: conifer),
+  variant(fill: forest, stroke: black, thickness: 2pt),
+  variant(fill: forest, stroke: conifer, thickness: 2pt),
 ) {
-  (align(horizon)[{i + 1}.], rect, [])
+  (align(horizon)[{i + 1}.], item, [])
 }
 
 #grid(
diff --git a/tests/typ/text/deco.typ b/tests/typ/text/deco.typ
index e0693ca3..a9f380b9 100644
--- a/tests/typ/text/deco.typ
+++ b/tests/typ/text/deco.typ
@@ -19,8 +19,8 @@
 #overline(underline[Running amongst the wolves.])
 
 ---
-#let redact = strike with (10pt, extent: 5%)
-#let highlight = strike with (
+#let redact = strike.with(10pt, extent: 5%)
+#let highlight = strike.with(
   stroke: rgb("abcdef88"),
   thickness: 10pt,
   extent: 5%,
diff --git a/tests/typ/utility/basics.typ b/tests/typ/utility/basics.typ
index 7fccc781..83d192c4 100644
--- a/tests/typ/utility/basics.typ
+++ b/tests/typ/utility/basics.typ
@@ -21,64 +21,4 @@
 // Test the `type` function.
 #test(type(1), "integer")
 #test(type(ltr), "direction")
-
----
-// Test the `repr` function.
-#test(repr(ltr), "ltr")
-#test(repr((1, 2, false, )), "(1, 2, false)")
-
----
-// Test the `join` function.
-#test(join(), none)
-#test(join(sep: false), none)
-#test(join(1), 1)
-#test(join("a", "b", "c"), "abc")
-#test("(" + join("a", "b", "c", sep: ", ") + ")", "(a, b, c)")
-
----
-// Test content joining.
-// Ref: true
-#join([One], [Two], [Three], sep: [, ]).
-
----
-// Error: 11-24 cannot join boolean with boolean
-#test(join(true, false))
-
----
-// Error: 11-29 cannot join string with integer
-#test(join("a", "b", sep: 1))
-
----
-// Test conversion functions.
-#test(int(false), 0)
-#test(int(true), 1)
-#test(int(10), 10)
-#test(int("150"), 150)
 #test(type(10 / 3), "float")
-#test(int(10 / 3), 3)
-#test(float(10), 10.0)
-#test(float("31.4e-1"), 3.14)
-#test(type(float(10)), "float")
-#test(str(123), "123")
-#test(str(50.14), "50.14")
-#test(len(str(10 / 3)) > 10, true)
-
----
-// Error: 6-10 cannot convert length to integer
-#int(10pt)
-
----
-// Error: 8-13 cannot convert function to float
-#float(float)
-
----
-// Error: 6-8 cannot convert content to string
-#str([])
-
----
-// Error: 6-12 invalid integer
-#int("nope")
-
----
-// Error: 8-15 invalid float
-#float("1.2.3")
diff --git a/tests/typ/utility/collection.typ b/tests/typ/utility/collection.typ
index e8be07b5..924200cb 100644
--- a/tests/typ/utility/collection.typ
+++ b/tests/typ/utility/collection.typ
@@ -2,42 +2,91 @@
 // Ref: false
 
 ---
-// Test the `len` function.
-#test(len(()), 0)
-#test(len(("A", "B", "C")), 3)
-#test(len("Hello World!"), 12)
-#test(len((a: 1, b: 2)), 2)
+// Test the `len` method.
+#test(().len(), 0)
+#test(("A", "B", "C").len(), 3)
+#test("Hello World!".len(), 12)
+#test((a: 1, b: 2).len(), 2)
 
 ---
-// Error: 5-7 missing argument: collection
-#len()
+// Test the `push` and `pop` methods.
+{
+  let tasks = (a: (1, 2, 3), b: (4, 5, 6))
+  tasks("a").pop()
+  tasks("b").push(7)
+  test(tasks("a"), (1, 2))
+  test(tasks("b"), (4, 5, 6, 7))
+}
 
 ---
-// Error: 6-10 expected string, array or dictionary, found length
-#len(12pt)
+// Test the `insert` and `remove` methods.
+{
+  let array = (0, 1, 2, 4, 5)
+  array.insert(3, 3)
+  test(array, range(6))
+  array.remove(1)
+  test(array, (0, 2, 3, 4, 5))
+}
 
 ---
-// Test the `upper` and `lower` functions.
-#let memes = "ArE mEmEs gReAt?";
-#test(lower(memes), "are memes great?")
-#test(upper(memes), "ARE MEMES GREAT?")
-#test(upper("Ελλάδα"), "ΕΛΛΆΔΑ")
+// Test the `find` method.
+#test(("Hi", "❤️", "Love").find("❤️"), 1)
+#test(("Bye", "💘", "Apart").find("❤️"), none)
 
 ---
-// Error: 8-9 expected string or content, found integer
-#upper(1)
+// Test the `slice` method.
+#test((1, 2, 3, 4).slice(2), (3, 4))
+#test(range(10).slice(2, 6), (2, 3, 4, 5))
+#test(range(10).slice(4, count: 3), (4, 5, 6))
 
 ---
-// Test the `sorted` function.
-#test(sorted(()), ())
-#test(sorted((true, false) * 10), (false,) * 10 + (true,) * 10)
-#test(sorted(("it", "the", "hi", "text")), ("hi", "it", "text", "the"))
-#test(sorted((2, 1, 3, 10, 5, 8, 6, -7, 2)), (-7, 1, 2, 2, 3, 5, 6, 8, 10))
+// Error: 3-31 array index out of bounds (index: 12, len: 10)
+{ range(10).slice(9, count: 3) }
 
 ---
-// Error: 9-21 cannot order string and integer
-#sorted((1, 2, "ab"))
+// Error: 2:17-2:19 missing argument: index
+#let numbers = ()
+{ numbers.insert() }
 
 ---
-// Error: 9-24 cannot order content and content
-#sorted(([Hi], [There]))
+// Test the `join` method.
+#test(().join(), none)
+#test((1,).join(), 1)
+#test(("a", "b", "c").join(), "abc")
+#test("(" + ("a", "b", "c").join(", ") + ")", "(a, b, c)")
+
+---
+// Error: 2-22 cannot join boolean with boolean
+{(true, false).join()}
+
+---
+// Error: 2-20 cannot join string with integer
+{("a", "b").join(1)}
+
+---
+// Test joining content.
+// Ref: true
+{([One], [Two], [Three]).join([, ], last: [ and ])}.
+
+---
+// Test the `sorted` method.
+#test(().sorted(), ())
+#test(((true, false) * 10).sorted(), (false,) * 10 + (true,) * 10)
+#test(("it", "the", "hi", "text").sorted(), ("hi", "it", "text", "the"))
+#test((2, 1, 3, 10, 5, 8, 6, -7, 2).sorted(), (-7, 1, 2, 2, 3, 5, 6, 8, 10))
+
+---
+// Error: 2-26 cannot order content and content
+{([Hi], [There]).sorted()}
+
+---
+// Test dictionary methods.
+#let dict = (a: 3, c: 2, b: 1)
+#test("c" in dict, true)
+#test(dict.len(), 3)
+#test(dict.values(), (3, 1, 2))
+#test(dict.pairs((k, v) => k + str(v)).join(), "a3b1c2")
+
+{ dict.remove("c") }
+#test("c" in dict, false)
+#test(dict, (a: 3, b: 1))
diff --git a/tests/typ/utility/math.typ b/tests/typ/utility/math.typ
index ec62dbd2..d4ac7aa2 100644
--- a/tests/typ/utility/math.typ
+++ b/tests/typ/utility/math.typ
@@ -2,6 +2,33 @@
 // Ref: false
 
 ---
+// Test conversion to numbers.
+#test(int(false), 0)
+#test(int(true), 1)
+#test(int(10), 10)
+#test(int("150"), 150)
+#test(int(10 / 3), 3)
+#test(float(10), 10.0)
+#test(float("31.4e-1"), 3.14)
+#test(type(float(10)), "float")
+
+---
+// Error: 6-10 cannot convert length to integer
+#int(10pt)
+
+---
+// Error: 8-13 cannot convert function to float
+#float(float)
+
+---
+// Error: 6-12 invalid integer
+#int("nope")
+
+---
+// Error: 8-15 invalid float
+#float("1.2.3")
+
+---
 // Test the `abs` function.
 #test(abs(-3), 3)
 #test(abs(3), 3)
diff --git a/tests/typ/utility/numbering.typ b/tests/typ/utility/numbering.typ
deleted file mode 100644
index 65dc12d0..00000000
--- a/tests/typ/utility/numbering.typ
+++ /dev/null
@@ -1,19 +0,0 @@
-// Test numbering formatting functions.
-
----
-#upper("Abc 8")
-#upper[def]
-
-#lower("SCREAMING MUST BE SILENCED in " + roman(1672) + " years")
-
-#for i in range(9) {
-    symbol(i)
-    [ and ]
-    roman(i)
-    [ for #i]
-    parbreak()
-}
-
----
-// Error: 9-11 must be at least zero
-#symbol(-1)
diff --git a/tests/typ/utility/string.typ b/tests/typ/utility/string.typ
new file mode 100644
index 00000000..9b57e833
--- /dev/null
+++ b/tests/typ/utility/string.typ
@@ -0,0 +1,52 @@
+// Test string related methods.
+// Ref: false
+
+---
+// Test conversion to string.
+#test(str(123), "123")
+#test(str(50.14), "50.14")
+#test(str(10 / 3).len() > 10, true)
+#test(repr(ltr), "ltr")
+#test(repr((1, 2, false, )), "(1, 2, false)")
+
+---
+// Error: 6-8 cannot convert content to string
+#str([])
+
+---
+// Test the `split` and `trim` methods.
+#test(
+    "Typst, LaTeX, Word, InDesign".split(",").map(s => s.trim()),
+    ("Typst", "LaTeX", "Word", "InDesign"),
+)
+
+---
+// Test the `upper` and `lower` functions.
+#let memes = "ArE mEmEs gReAt?";
+#test(lower(memes), "are memes great?")
+#test(upper(memes), "ARE MEMES GREAT?")
+#test(upper("Ελλάδα"), "ΕΛΛΆΔΑ")
+
+---
+// Error: 8-9 expected string or content, found integer
+#upper(1)
+
+---
+// Error: 9-11 must be at least zero
+#symbol(-1)
+
+---
+// Test integrated lower, upper and symbols.
+// Ref: true
+#upper("Abc 8")
+#upper[def]
+
+#lower("SCREAMING MUST BE SILENCED in " + roman(1672) + " years")
+
+#for i in range(9) {
+    symbol(i)
+    [ and ]
+    roman(i)
+    [ for #i]
+    parbreak()
+}
diff --git a/tools/support/typst.tmLanguage.json b/tools/support/typst.tmLanguage.json
index ce683699..ef7806c8 100644
--- a/tools/support/typst.tmLanguage.json
+++ b/tools/support/typst.tmLanguage.json
@@ -124,7 +124,7 @@
         },
         {
           "name": "keyword.other.typst",
-          "match": "(#)(as|in|with|from)\\b",
+          "match": "(#)(as|in|from)\\b",
           "captures": { "1": { "name": "punctuation.definition.keyword.typst" } }
         },
         {
@@ -168,19 +168,19 @@
         {
           "comment": "Function name",
           "name": "entity.name.function.typst",
-          "match": "((#)[[:alpha:]_][[:alnum:]._-]*!?)(?=\\[|\\()",
+          "match": "((#)[[:alpha:]_][[:alnum:]_-]*!?)(?=\\[|\\()",
           "captures": { "2": { "name": "punctuation.definition.function.typst" } }
         },
         {
           "comment": "Function arguments",
-          "begin": "(?<=#[[:alpha:]_][[:alnum:]._-]*!?)\\(",
+          "begin": "(?<=#[[:alpha:]_][[:alnum:]_-]*!?)\\(",
           "end": "\\)",
           "captures": { "0": { "name": "punctuation.definition.group.typst" } },
           "patterns": [{ "include": "#arguments" }]
         },
         {
           "name": "variable.interpolated.typst",
-          "match": "(#)[[:alpha:]_][[:alnum:]._-]*",
+          "match": "(#)[[:alpha:]_][[:alnum:]_-]*",
           "captures": { "1": { "name": "punctuation.definition.variable.typst" } }
         }
       ]
@@ -216,7 +216,7 @@
         },
         {
           "name": "keyword.operator.arithmetic.typst",
-          "match": "\\+|\\*|/|(?<![[:alpha:]_][[:alnum:]._-]*)-(?![:alnum:]_-]*[[:alpha:]_])"
+          "match": "\\+|\\*|/|(?<![[:alpha:]_][[:alnum:]_-]*)-(?![:alnum:]_-]*[[:alpha:]_])"
         },
         {
           "name": "keyword.operator.word.typst",
@@ -224,7 +224,7 @@
         },
         {
           "name": "keyword.other.typst",
-          "match": "\\b(pub|let|set|show|wrap|as|in|with|from)\\b"
+          "match": "\\b(pub|let|set|show|wrap|as|in|from)\\b"
         },
         {
           "name": "keyword.control.conditional.typst",
@@ -246,18 +246,18 @@
         {
           "comment": "Function name",
           "name": "entity.name.function.typst",
-          "match": "\\b[[:alpha:]_][[:alnum:]._-]*!?(?=(\\[|\\()|\\s+\\bwith\\b)"
+          "match": "\\b[[:alpha:]_][[:alnum:]_-]*!?(?=\\[|\\()"
         },
         {
           "comment": "Function arguments",
-          "begin": "(?<=\\b[[:alpha:]_][[:alnum:]._-]*!?|\\bwith\\b\\s+)\\(",
+          "begin": "(?<=\\b[[:alpha:]_][[:alnum:]_-]*!?)\\(",
           "end": "\\)",
           "captures": { "0": { "name": "punctuation.definition.group.typst" } },
           "patterns": [{ "include": "#arguments" }]
         },
         {
           "name": "variable.other.typst",
-          "match": "\\b[[:alpha:]_][[:alnum:]._-]*\\b"
+          "match": "\\b[[:alpha:]_][[:alnum:]_-]*\\b"
         },
         {
           "name": "meta.group.typst",
@@ -307,10 +307,6 @@
           "match": "\\b(\\d*)?\\.?\\d+([eE][+-]?\\d+)?\\b"
         },
         {
-          "name": "constant.other.color.typst",
-          "match": "#[0-9a-zA-Z]+\\b"
-        },
-        {
           "name": "string.quoted.double.typst",
           "begin": "\"",
           "end": "\"",
@@ -326,7 +322,7 @@
       "patterns": [
         {
           "name": "variable.parameter.typst",
-          "match": "\\b[[:alpha:]_][[:alnum:]._-]*(?=:)"
+          "match": "\\b[[:alpha:]_][[:alnum:]_-]*(?=:)"
         },
         { "include": "#code" }
       ]