From 4524539c2bc5f3a9f53bc57a1902264fc894969b Mon Sep 17 00:00:00 2001 From: Marmare314 <49279081+Marmare314@users.noreply.github.com> Date: Thu, 20 Apr 2023 11:05:11 +0200 Subject: forbid underscore as identifier closes #513 (#837) --- src/syntax/parser.rs | 72 ++++++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 62 insertions(+), 10 deletions(-) (limited to 'src/syntax/parser.rs') diff --git a/src/syntax/parser.rs b/src/syntax/parser.rs index 801fdfc8..389cf026 100644 --- a/src/syntax/parser.rs +++ b/src/syntax/parser.rs @@ -636,6 +636,17 @@ fn code_primary(p: &mut Parser, atomic: bool) { p.wrap(m, SyntaxKind::Closure); } } + SyntaxKind::Underscore if !atomic => { + p.eat(); + if p.at(SyntaxKind::Arrow) { + p.wrap(m, SyntaxKind::Params); + p.eat(); + code_expr(p); + p.wrap(m, SyntaxKind::Closure); + } else if let Some(underscore) = p.node_mut(m) { + underscore.convert_to_error("expected expression, found underscore"); + } + } SyntaxKind::LeftBrace => code_block(p), SyntaxKind::LeftBracket => content_block(p), @@ -718,6 +729,7 @@ fn with_paren(p: &mut Parser) { match kind { SyntaxKind::Array => validate_array(p, m), SyntaxKind::Dict => validate_dict(p, m), + SyntaxKind::Parenthesized => validate_parenthesized(p, m), _ => {} } p.wrap(m, kind); @@ -787,13 +799,19 @@ fn item(p: &mut Parser, keyed: bool) -> SyntaxKind { return SyntaxKind::Spread; } - code_expr(p); + if !p.eat_if(SyntaxKind::Underscore) { + code_expr(p); + } else { + return SyntaxKind::Underscore; + } if !p.eat_if(SyntaxKind::Colon) { return SyntaxKind::Int; } - code_expr(p); + if !p.eat_if(SyntaxKind::Underscore) { + code_expr(p); + } let kind = match p.node(m).map(SyntaxNode::kind) { Some(SyntaxKind::Ident) => SyntaxKind::Named, @@ -840,12 +858,12 @@ fn args(p: &mut Parser) { enum PatternKind { Ident, + Placeholder, Destructuring, } fn pattern(p: &mut Parser) -> PatternKind { let m = p.marker(); - if p.at(SyntaxKind::LeftParen) { let kind = collection(p, false); validate_destruct_pattern(p, m); @@ -856,6 +874,8 @@ fn pattern(p: &mut Parser) -> PatternKind { p.wrap(m, SyntaxKind::Destructuring); PatternKind::Destructuring } + } else if p.eat_if(SyntaxKind::Underscore) { + PatternKind::Placeholder } else { p.expect(SyntaxKind::Ident); PatternKind::Ident @@ -879,6 +899,7 @@ fn let_binding(p: &mut Parser) { p.wrap(m3, SyntaxKind::Params); } } + PatternKind::Placeholder => {} PatternKind::Destructuring => destructuring = true, } @@ -961,7 +982,9 @@ fn for_loop(p: &mut Parser) { pattern(p); if p.at(SyntaxKind::Comma) { p.expected("keyword `in`. did you mean to use a destructuring pattern?"); - p.eat_if(SyntaxKind::Ident); + if !p.eat_if(SyntaxKind::Ident) { + p.eat_if(SyntaxKind::Underscore); + } p.eat_if(SyntaxKind::In); } else { p.expect(SyntaxKind::In); @@ -1023,10 +1046,25 @@ fn return_stmt(p: &mut Parser) { p.wrap(m, SyntaxKind::FuncReturn); } +fn validate_parenthesized(p: &mut Parser, m: Marker) { + for child in p.post_process(m) { + let kind = child.kind(); + if kind == SyntaxKind::Underscore { + child.convert_to_error(eco_format!( + "expected expression, found {}", + kind.name() + )); + } + } +} + fn validate_array(p: &mut Parser, m: Marker) { for child in p.post_process(m) { let kind = child.kind(); - if kind == SyntaxKind::Named || kind == SyntaxKind::Keyed { + if kind == SyntaxKind::Named + || kind == SyntaxKind::Keyed + || kind == SyntaxKind::Underscore + { child.convert_to_error(eco_format!( "expected expression, found {}", kind.name() @@ -1114,7 +1152,10 @@ fn validate_params(p: &mut Parser, m: Marker) { child.make_erroneous(); } } - SyntaxKind::LeftParen | SyntaxKind::RightParen | SyntaxKind::Comma => {} + SyntaxKind::LeftParen + | SyntaxKind::RightParen + | SyntaxKind::Comma + | SyntaxKind::Underscore => {} kind => { child.convert_to_error(eco_format!( "expected identifier, named pair or argument sink, found {}", @@ -1137,6 +1178,8 @@ fn validate_args(p: &mut Parser, m: Marker) { )); child.make_erroneous(); } + } else if child.kind() == SyntaxKind::Underscore { + child.convert_to_error("unexpected underscore"); } } } @@ -1147,7 +1190,7 @@ fn validate_destruct_pattern(p: &mut Parser, m: Marker) { for child in p.post_process(m) { match child.kind() { SyntaxKind::Ident => { - if child.text() != "_" && !used.insert(child.text().clone()) { + if !used.insert(child.text().clone()) { child.convert_to_error( "at most one binding per identifier is allowed", ); @@ -1172,7 +1215,7 @@ fn validate_destruct_pattern(p: &mut Parser, m: Marker) { continue; } - if within.text() != "_" && !used.insert(within.text().clone()) { + if !used.insert(within.text().clone()) { within.convert_to_error( "at most one binding per identifier is allowed", ); @@ -1189,7 +1232,9 @@ fn validate_destruct_pattern(p: &mut Parser, m: Marker) { } let Some(within) = child.children_mut().last_mut() else { return }; - if within.kind() != SyntaxKind::Ident { + if within.kind() != SyntaxKind::Ident + && within.kind() != SyntaxKind::Underscore + { within.convert_to_error(eco_format!( "expected identifier, found {}", within.kind().name(), @@ -1197,7 +1242,10 @@ fn validate_destruct_pattern(p: &mut Parser, m: Marker) { child.make_erroneous(); } } - SyntaxKind::LeftParen | SyntaxKind::RightParen | SyntaxKind::Comma => {} + SyntaxKind::LeftParen + | SyntaxKind::RightParen + | SyntaxKind::Comma + | SyntaxKind::Underscore => {} kind => { child.convert_to_error(eco_format!( "expected identifier or destructuring sink, found {}", @@ -1313,6 +1361,10 @@ impl<'s> Parser<'s> { self.nodes.get(m.0) } + fn node_mut(&mut self, m: Marker) -> Option<&mut SyntaxNode> { + self.nodes.get_mut(m.0) + } + fn post_process(&mut self, m: Marker) -> impl Iterator { self.nodes[m.0..] .iter_mut() -- cgit v1.2.3