Merge some modules

1 files changed, 0 insertions, 161 deletions

diff --git a/src/eval/scope.rs b/src/eval/scope.rs
deleted file mode 100644
index 1ab7032c..00000000
--- a/src/eval/scope.rs
+++ /dev/null
@@ -1,161 +0,0 @@
-use std::collections::BTreeMap;
-use std::fmt::{self, Debug, Formatter};
-use std::hash::Hash;
-
-use super::{Args, Func, Node, Value, Vm};
-use crate::diag::{SourceResult, StrResult};
-use crate::util::EcoString;
-
-/// A stack of scopes.
-#[derive(Debug, Default, Clone)]
-pub struct Scopes<'a> {
-    /// The active scope.
-    pub top: Scope,
-    /// The stack of lower scopes.
-    pub scopes: Vec<Scope>,
-    /// The base scope.
-    pub base: Option<&'a Scope>,
-}
-
-impl<'a> Scopes<'a> {
-    /// Create a new, empty hierarchy of scopes.
-    pub fn new(base: Option<&'a Scope>) -> Self {
-        Self { top: Scope::new(), scopes: vec![], base }
-    }
-
-    /// Enter a new scope.
-    pub fn enter(&mut self) {
-        self.scopes.push(std::mem::take(&mut self.top));
-    }
-
-    /// Exit the topmost scope.
-    ///
-    /// This panics if no scope was entered.
-    pub fn exit(&mut self) {
-        self.top = self.scopes.pop().expect("no pushed scope");
-    }
-
-    /// Try to access a variable immutably.
-    pub fn get(&self, var: &str) -> StrResult<&Value> {
-        Ok(std::iter::once(&self.top)
-            .chain(self.scopes.iter().rev())
-            .chain(self.base.into_iter())
-            .find_map(|scope| scope.get(var))
-            .ok_or("unknown variable")?)
-    }
-
-    /// Try to access a variable mutably.
-    pub fn get_mut(&mut self, var: &str) -> StrResult<&mut Value> {
-        std::iter::once(&mut self.top)
-            .chain(&mut self.scopes.iter_mut().rev())
-            .find_map(|scope| scope.get_mut(var))
-            .ok_or_else(|| {
-                if self.base.map_or(false, |base| base.get(var).is_some()) {
-                    "cannot mutate a constant"
-                } else {
-                    "unknown variable"
-                }
-            })?
-    }
-}
-
-/// A map from binding names to values.
-#[derive(Default, Clone, Hash)]
-pub struct Scope(BTreeMap<EcoString, Slot>);
-
-impl Scope {
-    /// Create a new empty scope.
-    pub fn new() -> Self {
-        Self::default()
-    }
-
-    /// Bind a value to a name.
-    pub fn define(&mut self, name: impl Into<EcoString>, value: impl Into<Value>) {
-        self.0.insert(name.into(), Slot::new(value.into(), Kind::Normal));
-    }
-
-    /// Define a function through a native rust function.
-    pub fn def_fn(
-        &mut self,
-        name: &'static str,
-        func: fn(&mut Vm, &mut Args) -> SourceResult<Value>,
-    ) {
-        self.define(name, Func::from_fn(name, func));
-    }
-
-    /// Define a function through a native rust node.
-    pub fn def_node<T: Node>(&mut self, name: &'static str) {
-        self.define(name, Func::from_node::<T>(name));
-    }
-
-    /// Define a captured, immutable binding.
-    pub fn define_captured(
-        &mut self,
-        var: impl Into<EcoString>,
-        value: impl Into<Value>,
-    ) {
-        self.0.insert(var.into(), Slot::new(value.into(), Kind::Captured));
-    }
-
-    /// Try to access a variable immutably.
-    pub fn get(&self, var: &str) -> Option<&Value> {
-        self.0.get(var).map(Slot::read)
-    }
-
-    /// Try to access a variable mutably.
-    pub fn get_mut(&mut self, var: &str) -> Option<StrResult<&mut Value>> {
-        self.0.get_mut(var).map(Slot::write)
-    }
-
-    /// Iterate over all definitions.
-    pub fn iter(&self) -> impl Iterator<Item = (&str, &Value)> {
-        self.0.iter().map(|(k, v)| (k.as_str(), v.read()))
-    }
-}
-
-impl Debug for Scope {
-    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
-        f.write_str("Scope ")?;
-        f.debug_map()
-            .entries(self.0.iter().map(|(k, v)| (k, v.read())))
-            .finish()
-    }
-}
-
-/// A slot where a value is stored.
-#[derive(Clone, Hash)]
-struct Slot {
-    /// The stored value.
-    value: Value,
-    /// The kind of slot, determines how the value can be accessed.
-    kind: Kind,
-}
-
-/// The different kinds of slots.
-#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
-enum Kind {
-    /// A normal, mutable binding.
-    Normal,
-    /// A captured copy of another variable.
-    Captured,
-}
-
-impl Slot {
-    /// Create a new slot.
-    fn new(value: Value, kind: Kind) -> Self {
-        Self { value, kind }
-    }
-
-    /// Read the value.
-    fn read(&self) -> &Value {
-        &self.value
-    }
-
-    /// Try to write to the value.
-    fn write(&mut self) -> StrResult<&mut Value> {
-        match self.kind {
-            Kind::Normal => Ok(&mut self.value),
-            Kind::Captured => Err("cannot mutate a captured variable")?,
-        }
-    }
-}