SpanWith trait ↔

7 files changed, 46 insertions, 37 deletions

diff --git a/src/compute/value.rs b/src/compute/value.rs
index 95219a5c..ef36e5d8 100644
--- a/src/compute/value.rs
+++ b/src/compute/value.rs
@@ -11,7 +11,7 @@ use crate::color::RgbaColor;
 use crate::layout::{Command, Commands, Dir, LayoutContext, SpecAlign};
 use crate::length::{Length, ScaleLength};
 use crate::paper::Paper;
-use crate::syntax::{Ident, Span, Spanned, SyntaxNode, SyntaxTree};
+use crate::syntax::{Ident, Span, SpanWith, Spanned, SyntaxNode, SyntaxTree};
 use crate::{DynFuture, Feedback, Pass};
 
 /// A computational value.
@@ -76,10 +76,8 @@ impl Spanned<Value> {
                 for entry in table.into_values() {
                     if let Some(last_end) = end {
                         let span = Span::new(last_end, entry.key.start);
-                        commands.push(Command::LayoutSyntaxTree(vec![Spanned::new(
-                            SyntaxNode::Spacing,
-                            span,
-                        )]));
+                        let tree = vec![SyntaxNode::Spacing.span_with(span)];
+                        commands.push(Command::LayoutSyntaxTree(tree));
                     }
 
                     end = Some(entry.val.span.end);
@@ -89,10 +87,11 @@ impl Spanned<Value> {
             }
 
             // Format with debug.
-            val => vec![Command::LayoutSyntaxTree(vec![Spanned::new(
-                SyntaxNode::Text(format!("{:?}", val)),
-                self.span,
-            )])],
+            val => {
+                let fmt = format!("{:?}", val);
+                let tree = vec![SyntaxNode::Text(fmt).span_with(self.span)];
+                vec![Command::LayoutSyntaxTree(tree)]
+            }
         }
     }
 }
diff --git a/src/layout/tree.rs b/src/layout/tree.rs
index 19bff091..82a91131 100644
--- a/src/layout/tree.rs
+++ b/src/layout/tree.rs
@@ -5,7 +5,7 @@ use super::text::{layout_text, TextContext};
 use super::*;
 use crate::style::LayoutStyle;
 use crate::syntax::{
-    CallExpr, Code, Decoration, Heading, Span, Spanned, SyntaxNode, SyntaxTree,
+    CallExpr, Code, Decoration, Heading, Span, SpanWith, Spanned, SyntaxNode, SyntaxTree,
 };
 use crate::{DynFuture, Feedback, Pass};
 
@@ -53,8 +53,8 @@ impl<'a> TreeLayouter<'a> {
     }
 
     async fn layout_node(&mut self, node: &Spanned<SyntaxNode>) {
-        let decorate = |this: &mut Self, deco| {
-            this.feedback.decorations.push(Spanned::new(deco, node.span));
+        let decorate = |this: &mut Self, deco: Decoration| {
+            this.feedback.decorations.push(deco.span_with(node.span));
         };
 
         match &node.v {
@@ -87,7 +87,7 @@ impl<'a> TreeLayouter<'a> {
             SyntaxNode::Code(block) => self.layout_code(block).await,
 
             SyntaxNode::Call(call) => {
-                self.layout_call(Spanned::new(call, node.span)).await;
+                self.layout_call(call.span_with(node.span)).await;
             }
         }
     }
@@ -167,7 +167,7 @@ impl<'a> TreeLayouter<'a> {
         };
 
         let val = call.v.eval(&ctx, &mut self.feedback).await;
-        let commands = Spanned::new(val, call.span).into_commands();
+        let commands = val.span_with(call.span).into_commands();
 
         for command in commands {
             self.execute_command(command, call.span).await;
diff --git a/src/parse/parser.rs b/src/parse/parser.rs
index 2ff30397..bbd7ee1d 100644
--- a/src/parse/parser.rs
+++ b/src/parse/parser.rs
@@ -113,7 +113,7 @@ impl Parser<'_> {
 
                 let lang = lang.and_then(|lang| {
                     if let Some(ident) = Ident::new(lang.v) {
-                        Some(Spanned::new(ident, lang.span))
+                        Some(ident.span_with(lang.span))
                     } else {
                         error!(@self.feedback, lang.span, "invalid identifier");
                         None
@@ -166,7 +166,7 @@ impl Parser<'_> {
         }
 
         let span = Span::new(start, self.pos());
-        let level = Spanned::new(level, span);
+        let level = level.span_with(span);
 
         if level.v > 5 {
             warning!(
@@ -185,7 +185,7 @@ impl Parser<'_> {
         }
 
         let span = Span::new(start, self.pos());
-        Spanned::new(Heading { level, tree }, span)
+        Heading { level, tree }.span_with(span)
     }
 }
 
@@ -203,7 +203,7 @@ impl Parser<'_> {
         self.skip_ws();
         let name = self.parse_ident().unwrap_or_else(|| {
             self.expected_found_or_at("function name", before_name);
-            Spanned::new(Ident(String::new()), Span::at(before_name))
+            Ident(String::new()).span_with(Span::at(before_name))
         });
 
         self.skip_ws();
@@ -224,7 +224,7 @@ impl Parser<'_> {
             let item = self.parse_bracket_call(true);
             let span = item.span;
             let t = vec![item.map(SyntaxNode::Call)];
-            args.push(SpannedEntry::val(Spanned::new(Expr::Tree(t), span)));
+            args.push(SpannedEntry::val(Expr::Tree(t).span_with(span)));
             (true, span.end)
         } else {
             self.tokens.pop_mode();
@@ -244,11 +244,11 @@ impl Parser<'_> {
             let body_span = self.end_group();
 
             let expr = Expr::Tree(body);
-            args.push(SpannedEntry::val(Spanned::new(expr, body_span)));
+            args.push(SpannedEntry::val(expr.span_with(body_span)));
             span.expand(body_span);
         }
 
-        Spanned::new(CallExpr { name, args }, span)
+        CallExpr { name, args }.span_with(span)
     }
 
     fn parse_paren_call(&mut self, name: Spanned<Ident>) -> Spanned<CallExpr> {
@@ -256,7 +256,7 @@ impl Parser<'_> {
         let args = self.parse_table_contents().0;
         let args_span = self.end_group();
         let span = Span::merge(name.span, args_span);
-        Spanned::new(CallExpr { name, args }, span)
+        CallExpr { name, args }.span_with(span)
     }
 }
 
@@ -305,7 +305,7 @@ impl Parser<'_> {
                 table.insert(key.v.0, SpannedEntry::new(key.span, val));
                 self.feedback
                     .decorations
-                    .push(Spanned::new(Decoration::TableKey, key.span));
+                    .push(Decoration::TableKey.span_with(key.span));
             } else {
                 table.push(SpannedEntry::val(val));
             }
@@ -364,7 +364,7 @@ impl Parser<'_> {
                 if let Some(right) = parse_operand(self) {
                     let span = Span::merge(left.span, right.span);
                     let v = op(Box::new(left), Box::new(right));
-                    left = Spanned::new(v, span);
+                    left = v.span_with(span);
                     self.skip_ws();
                     continue;
                 }
@@ -385,7 +385,7 @@ impl Parser<'_> {
             self.skip_ws();
             if let Some(factor) = self.parse_factor() {
                 let span = Span::merge(hyph.span, factor.span);
-                Some(Spanned::new(Expr::Neg(Box::new(factor)), span))
+                Some(Expr::Neg(Box::new(factor)).span_with(span))
             } else {
                 error!(@self.feedback, hyph.span, "dangling minus");
                 None
@@ -400,7 +400,7 @@ impl Parser<'_> {
         Some(match token {
             // This could be a function call or an identifier.
             Token::Ident(id) => {
-                let name = Spanned::new(Ident(id.to_string()), span);
+                let name = Ident(id.to_string()).span_with(span);
                 self.eat();
                 self.skip_ws();
                 if self.check(Token::LeftParen) {
@@ -445,7 +445,7 @@ impl Parser<'_> {
                     Expr::Table(table)
                 };
 
-                Spanned::new(expr, span)
+                expr.span_with(span)
             }
 
             // This is a content expression.
@@ -457,14 +457,14 @@ impl Parser<'_> {
 
                 self.tokens.pop_mode();
                 let span = self.end_group();
-                Spanned::new(Expr::Tree(tree), span)
+                Expr::Tree(tree).span_with(span)
             }
 
             // This is a bracketed function call.
             Token::LeftBracket => {
                 let call = self.parse_bracket_call(false);
                 let tree = vec![call.map(SyntaxNode::Call)];
-                Spanned::new(Expr::Tree(tree), span)
+                Expr::Tree(tree).span_with(span)
             }
 
             _ => return None,
@@ -587,7 +587,7 @@ impl<'s> Parser<'s> {
 
     fn with_span<T>(&mut self, v: T) -> Spanned<T> {
         let span = self.eat().expect("expected token").span;
-        Spanned::new(v, span)
+        v.span_with(span)
     }
 
     fn eof(&mut self) -> bool {
diff --git a/src/parse/tests.rs b/src/parse/tests.rs
index 70517bd8..209717f9 100644
--- a/src/parse/tests.rs
+++ b/src/parse/tests.rs
@@ -187,7 +187,7 @@ where
 }
 
 pub fn s<T>(sl: usize, sc: usize, el: usize, ec: usize, v: T) -> Spanned<T> {
-    Spanned::new(v, Span::new(Pos::new(sl, sc), Pos::new(el, ec)))
+    v.span_with(Span::new(Pos::new(sl, sc), Pos::new(el, ec)))
 }
 
 // Enables tests to optionally specify spans.
diff --git a/src/parse/tokenizer.rs b/src/parse/tokenizer.rs
index a251d960..d3605309 100644
--- a/src/parse/tokenizer.rs
+++ b/src/parse/tokenizer.rs
@@ -5,7 +5,7 @@ use std::str::Chars;
 use unicode_xid::UnicodeXID;
 
 use crate::length::Length;
-use crate::syntax::{Pos, Span, Spanned, Token};
+use crate::syntax::{Pos, Span, SpanWith, Spanned, Token};
 
 use Token::*;
 use TokenMode::*;
@@ -236,7 +236,7 @@ impl<'s> Tokens<'s> {
             let end = self.pos();
 
             let lang = if !lang.is_empty() {
-                Some(Spanned::new(lang, Span::new(start, end)))
+                Some(lang.span_with(Span::new(start, end)))
             } else {
                 None
             };
diff --git a/src/syntax/span.rs b/src/syntax/span.rs
index 6f5420d4..cda35ec0 100644
--- a/src/syntax/span.rs
+++ b/src/syntax/span.rs
@@ -17,6 +17,16 @@ pub trait Offset {
     fn offset(self, by: Pos) -> Self;
 }
 
+/// Annotate a value with a span.
+pub trait SpanWith: Sized {
+    /// Wraps `self` in a `Spanned` with the given span.
+    fn span_with(self, span: Span) -> Spanned<Self> {
+        Spanned::new(self, span)
+    }
+}
+
+impl<T> SpanWith for T {}
+
 /// A vector of spanned values of type `T`.
 pub type SpanVec<T> = Vec<Spanned<T>>;
 
diff --git a/src/syntax/tree.rs b/src/syntax/tree.rs
index 8c4270e2..5327bfa4 100644
--- a/src/syntax/tree.rs
+++ b/src/syntax/tree.rs
@@ -2,7 +2,7 @@
 
 use std::fmt::{self, Debug, Formatter};
 
-use super::span::{SpanVec, Spanned};
+use super::span::{SpanVec, SpanWith, Spanned};
 use super::Decoration;
 use crate::color::RgbaColor;
 use crate::compute::table::{SpannedEntry, Table};
@@ -203,7 +203,7 @@ impl TableExpr {
 
             for (key, entry) in self.iter() {
                 let val = entry.val.v.eval(ctx, f).await;
-                let spanned = Spanned::new(val, entry.val.span);
+                let spanned = val.span_with(entry.val.span);
                 let entry = SpannedEntry::new(entry.key, spanned);
                 table.insert(key, entry);
             }
@@ -230,12 +230,12 @@ impl CallExpr {
         if let Some(func) = ctx.scope.func(name) {
             let pass = func(span, args, ctx.clone()).await;
             f.extend(pass.feedback);
-            f.decorations.push(Spanned::new(Decoration::Resolved, span));
+            f.decorations.push(Decoration::Resolved.span_with(span));
             pass.output
         } else {
             if !name.is_empty() {
                 error!(@f, span, "unknown function");
-                f.decorations.push(Spanned::new(Decoration::Unresolved, span));
+                f.decorations.push(Decoration::Unresolved.span_with(span));
             }
             Value::Table(args)
         }