Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/syntax/src/ast/prec.rs')
-rw-r--r--crates/syntax/src/ast/prec.rs49
1 files changed, 37 insertions, 12 deletions
diff --git a/crates/syntax/src/ast/prec.rs b/crates/syntax/src/ast/prec.rs
index 5d33f132ac..0c4da76299 100644
--- a/crates/syntax/src/ast/prec.rs
+++ b/crates/syntax/src/ast/prec.rs
@@ -7,7 +7,7 @@ use crate::{
#[derive(Debug, Clone, Copy, PartialEq, PartialOrd)]
pub enum ExprPrecedence {
- // return, break, yield, closures
+ // return val, break val, yield val, closures
Jump,
// = += -= *= /= %= &= |= ^= <<= >>=
Assign,
@@ -35,10 +35,27 @@ pub enum ExprPrecedence {
Cast,
// unary - * ! & &mut
Prefix,
- // paths, loops, function calls, array indexing, field expressions, method calls
+ // function calls, array indexing, field expressions, method calls
+ Postfix,
+ // paths, loops,
Unambiguous,
}
+impl ExprPrecedence {
+ pub fn needs_parentheses_in(self, other: ExprPrecedence) -> bool {
+ match other {
+ ExprPrecedence::Unambiguous => false,
+ // postfix ops have higher precedence than any other operator, so we need to wrap
+ // any inner expression that is below
+ ExprPrecedence::Postfix => self < ExprPrecedence::Postfix,
+ // We need to wrap all binary like things, thats everything below prefix except for
+ // jumps (as those are prefix operations as well)
+ ExprPrecedence::Prefix => ExprPrecedence::Jump < self && self < ExprPrecedence::Prefix,
+ parent => self <= parent,
+ }
+ }
+}
+
#[derive(PartialEq, Debug)]
pub enum Fixity {
/// The operator is left-associative
@@ -56,11 +73,18 @@ pub fn precedence(expr: &ast::Expr) -> ExprPrecedence {
Some(_) => ExprPrecedence::Unambiguous,
},
+ Expr::BreakExpr(e) if e.expr().is_some() => ExprPrecedence::Jump,
+ Expr::BecomeExpr(e) if e.expr().is_some() => ExprPrecedence::Jump,
+ Expr::ReturnExpr(e) if e.expr().is_some() => ExprPrecedence::Jump,
+ Expr::YeetExpr(e) if e.expr().is_some() => ExprPrecedence::Jump,
+ Expr::YieldExpr(e) if e.expr().is_some() => ExprPrecedence::Jump,
+
Expr::BreakExpr(_)
- | Expr::ContinueExpr(_)
+ | Expr::BecomeExpr(_)
| Expr::ReturnExpr(_)
| Expr::YeetExpr(_)
- | Expr::YieldExpr(_) => ExprPrecedence::Jump,
+ | Expr::YieldExpr(_)
+ | Expr::ContinueExpr(_) => ExprPrecedence::Unambiguous,
Expr::RangeExpr(..) => ExprPrecedence::Range,
@@ -89,27 +113,27 @@ pub fn precedence(expr: &ast::Expr) -> ExprPrecedence {
Expr::LetExpr(_) | Expr::PrefixExpr(_) | Expr::RefExpr(_) => ExprPrecedence::Prefix,
+ Expr::AwaitExpr(_)
+ | Expr::CallExpr(_)
+ | Expr::FieldExpr(_)
+ | Expr::IndexExpr(_)
+ | Expr::MethodCallExpr(_)
+ | Expr::TryExpr(_) => ExprPrecedence::Postfix,
+
Expr::ArrayExpr(_)
| Expr::AsmExpr(_)
- | Expr::AwaitExpr(_)
- | Expr::BecomeExpr(_)
| Expr::BlockExpr(_)
- | Expr::CallExpr(_)
- | Expr::FieldExpr(_)
| Expr::ForExpr(_)
| Expr::FormatArgsExpr(_)
| Expr::IfExpr(_)
- | Expr::IndexExpr(_)
| Expr::Literal(_)
| Expr::LoopExpr(_)
| Expr::MacroExpr(_)
| Expr::MatchExpr(_)
- | Expr::MethodCallExpr(_)
| Expr::OffsetOfExpr(_)
| Expr::ParenExpr(_)
| Expr::PathExpr(_)
| Expr::RecordExpr(_)
- | Expr::TryExpr(_)
| Expr::TupleExpr(_)
| Expr::UnderscoreExpr(_)
| Expr::WhileExpr(_) => ExprPrecedence::Unambiguous,
@@ -128,7 +152,7 @@ impl Expr {
// - https://github.com/rust-lang/rust/blob/b6852428a8ea9728369b64b9964cad8e258403d3/compiler/rustc_ast/src/util/parser.rs#L296
/// Returns `true` if `self` would need to be wrapped in parentheses given that its parent is `parent`.
- pub fn needs_parens_in(&self, parent: SyntaxNode) -> bool {
+ pub fn needs_parens_in(&self, parent: &SyntaxNode) -> bool {
match_ast! {
match parent {
ast::Expr(e) => self.needs_parens_in_expr(&e),
@@ -384,6 +408,7 @@ impl Expr {
BreakExpr(e) => e.expr().is_none(),
ContinueExpr(_) => true,
YieldExpr(e) => e.expr().is_none(),
+ BecomeExpr(e) => e.expr().is_none(),
_ => false,
}
}