From 89e56c364f3d0a9d5a12ae488185abc1ea69df4a Mon Sep 17 00:00:00 2001
From: Aleksey Kladov <aleksey.kladov@gmail.com>
Date: Fri, 24 Aug 2018 11:45:14 +0300
Subject: Labeled expressions
---
crates/libsyntax2/src/grammar.ron | 5 +-
crates/libsyntax2/src/grammar/expressions/atom.rs | 61 +++++++++++++++------
crates/libsyntax2/src/grammar/mod.rs | 2 +-
crates/libsyntax2/src/syntax_kinds/generated.rs | 10 ++--
.../tests/data/parser/inline/0107_label.rs | 5 ++
.../tests/data/parser/inline/0107_label.txt | 63 ++++++++++++++++++++++
6 files changed, 123 insertions(+), 23 deletions(-)
create mode 100644 crates/libsyntax2/tests/data/parser/inline/0107_label.rs
create mode 100644 crates/libsyntax2/tests/data/parser/inline/0107_label.txt
(limited to 'crates/libsyntax2')
diff --git a/crates/libsyntax2/src/grammar.ron b/crates/libsyntax2/src/grammar.ron
index dff88cc4a..52764e664 100644
--- a/crates/libsyntax2/src/grammar.ron
+++ b/crates/libsyntax2/src/grammar.ron
@@ -161,11 +161,12 @@ Grammar(
"PATH_EXPR",
"LAMBDA_EXPR",
"IF_EXPR",
- "WHILE_EXPR",
"LOOP_EXPR",
+ "FOR_EXPR",
+ "WHILE_EXPR",
"CONTINUE_EXPR",
"BREAK_EXPR",
- "FOR_EXPR",
+ "LABEL",
"BLOCK_EXPR",
"RETURN_EXPR",
"MATCH_EXPR",
diff --git a/crates/libsyntax2/src/grammar/expressions/atom.rs b/crates/libsyntax2/src/grammar/expressions/atom.rs
index 9f470d561..9d98340af 100644
--- a/crates/libsyntax2/src/grammar/expressions/atom.rs
+++ b/crates/libsyntax2/src/grammar/expressions/atom.rs
@@ -30,7 +30,7 @@ pub(super) const ATOM_EXPR_FIRST: TokenSet =
token_set_union![
LITERAL_FIRST,
token_set![L_PAREN, PIPE, MOVE_KW, IF_KW, WHILE_KW, MATCH_KW, UNSAFE_KW, L_CURLY, RETURN_KW,
- IDENT, SELF_KW, SUPER_KW, COLONCOLON, BREAK_KW, CONTINUE_KW ],
+ IDENT, SELF_KW, SUPER_KW, COLONCOLON, BREAK_KW, CONTINUE_KW, LIFETIME ],
];
pub(super) fn atom_expr(p: &mut Parser, r: Restrictions) -> Option<CompletedMarker> {
@@ -48,9 +48,24 @@ pub(super) fn atom_expr(p: &mut Parser, r: Restrictions) -> Option<CompletedMark
PIPE => lambda_expr(p),
MOVE_KW if la == PIPE => lambda_expr(p),
IF_KW => if_expr(p),
- WHILE_KW => while_expr(p),
- LOOP_KW => loop_expr(p),
- FOR_KW => for_expr(p),
+
+ LOOP_KW => loop_expr(p, None),
+ FOR_KW => for_expr(p, None),
+ WHILE_KW => while_expr(p, None),
+ LIFETIME if la == COLON => {
+ let m = p.start();
+ label(p);
+ match p.current() {
+ LOOP_KW => loop_expr(p, Some(m)),
+ FOR_KW => for_expr(p, Some(m)),
+ WHILE_KW => while_expr(p, Some(m)),
+ _ => {
+ p.error("expected a loop");
+ return None;
+ }
+ }
+ }
+
MATCH_KW => match_expr(p),
UNSAFE_KW if la == L_CURLY => block_expr(p),
L_CURLY => block_expr(p),
@@ -164,39 +179,53 @@ fn if_expr(p: &mut Parser) -> CompletedMarker {
m.complete(p, IF_EXPR)
}
-// test while_expr
+// test label
// fn foo() {
-// while true {};
-// while let Some(x) = it.next() {};
+// 'a: loop {}
+// 'b: while true {}
+// 'c: for x in () {}
// }
-fn while_expr(p: &mut Parser) -> CompletedMarker {
- assert!(p.at(WHILE_KW));
+fn label(p: &mut Parser) {
+ assert!(p.at(LIFETIME) && p.nth(1) == COLON);
let m = p.start();
p.bump();
- cond(p);
- block(p);
- m.complete(p, WHILE_EXPR)
+ p.bump();
+ m.complete(p, LABEL);
}
// test loop_expr
// fn foo() {
// loop {};
// }
-fn loop_expr(p: &mut Parser) -> CompletedMarker {
+fn loop_expr(p: &mut Parser, m: Option<Marker>) -> CompletedMarker {
assert!(p.at(LOOP_KW));
- let m = p.start();
+ let m = m.unwrap_or_else(|| p.start());
p.bump();
block(p);
m.complete(p, LOOP_EXPR)
}
+// test while_expr
+// fn foo() {
+// while true {};
+// while let Some(x) = it.next() {};
+// }
+fn while_expr(p: &mut Parser, m: Option<Marker>) -> CompletedMarker {
+ assert!(p.at(WHILE_KW));
+ let m = m.unwrap_or_else(|| p.start());
+ p.bump();
+ cond(p);
+ block(p);
+ m.complete(p, WHILE_EXPR)
+}
+
// test for_expr
// fn foo() {
// for x in [] {};
// }
-fn for_expr(p: &mut Parser) -> CompletedMarker {
+fn for_expr(p: &mut Parser, m: Option<Marker>) -> CompletedMarker {
assert!(p.at(FOR_KW));
- let m = p.start();
+ let m = m.unwrap_or_else(|| p.start());
p.bump();
patterns::pattern(p);
p.expect(IN_KW);
diff --git a/crates/libsyntax2/src/grammar/mod.rs b/crates/libsyntax2/src/grammar/mod.rs
index 0f168eb60..25887921b 100644
--- a/crates/libsyntax2/src/grammar/mod.rs
+++ b/crates/libsyntax2/src/grammar/mod.rs
@@ -32,7 +32,7 @@ mod type_params;
mod types;
use {
- parser_api::{CompletedMarker, Parser, TokenSet},
+ parser_api::{Marker, CompletedMarker, Parser, TokenSet},
SyntaxKind::{self, *},
};
diff --git a/crates/libsyntax2/src/syntax_kinds/generated.rs b/crates/libsyntax2/src/syntax_kinds/generated.rs
index 82b6c89cf..61d527f93 100644
--- a/crates/libsyntax2/src/syntax_kinds/generated.rs
+++ b/crates/libsyntax2/src/syntax_kinds/generated.rs
@@ -157,11 +157,12 @@ pub enum SyntaxKind {
PATH_EXPR,
LAMBDA_EXPR,
IF_EXPR,
- WHILE_EXPR,
LOOP_EXPR,
+ FOR_EXPR,
+ WHILE_EXPR,
CONTINUE_EXPR,
BREAK_EXPR,
- FOR_EXPR,
+ LABEL,
BLOCK_EXPR,
RETURN_EXPR,
MATCH_EXPR,
@@ -406,11 +407,12 @@ impl SyntaxKind {
PATH_EXPR => &SyntaxInfo { name: "PATH_EXPR" },
LAMBDA_EXPR => &SyntaxInfo { name: "LAMBDA_EXPR" },
IF_EXPR => &SyntaxInfo { name: "IF_EXPR" },
- WHILE_EXPR => &SyntaxInfo { name: "WHILE_EXPR" },
LOOP_EXPR => &SyntaxInfo { name: "LOOP_EXPR" },
+ FOR_EXPR => &SyntaxInfo { name: "FOR_EXPR" },
+ WHILE_EXPR => &SyntaxInfo { name: "WHILE_EXPR" },
CONTINUE_EXPR => &SyntaxInfo { name: "CONTINUE_EXPR" },
BREAK_EXPR => &SyntaxInfo { name: "BREAK_EXPR" },
- FOR_EXPR => &SyntaxInfo { name: "FOR_EXPR" },
+ LABEL => &SyntaxInfo { name: "LABEL" },
BLOCK_EXPR => &SyntaxInfo { name: "BLOCK_EXPR" },
RETURN_EXPR => &SyntaxInfo { name: "RETURN_EXPR" },
MATCH_EXPR => &SyntaxInfo { name: "MATCH_EXPR" },
diff --git a/crates/libsyntax2/tests/data/parser/inline/0107_label.rs b/crates/libsyntax2/tests/data/parser/inline/0107_label.rs
new file mode 100644
index 000000000..48e83f263
--- /dev/null
+++ b/crates/libsyntax2/tests/data/parser/inline/0107_label.rs
@@ -0,0 +1,5 @@
+fn foo() {
+ 'a: loop {}
+ 'b: while true {}
+ 'c: for x in () {}
+}
diff --git a/crates/libsyntax2/tests/data/parser/inline/0107_label.txt b/crates/libsyntax2/tests/data/parser/inline/0107_label.txt
new file mode 100644
index 000000000..66ba792b8
--- /dev/null
+++ b/crates/libsyntax2/tests/data/parser/inline/0107_label.txt
@@ -0,0 +1,63 @@
+FILE@[0; 74)
+ FN_DEF@[0; 73)
+ FN_KW@[0; 2)
+ WHITESPACE@[2; 3)
+ NAME@[3; 6)
+ IDENT@[3; 6) "foo"
+ PARAM_LIST@[6; 8)
+ L_PAREN@[6; 7)
+ R_PAREN@[7; 8)
+ WHITESPACE@[8; 9)
+ BLOCK_EXPR@[9; 73)
+ L_CURLY@[9; 10)
+ WHITESPACE@[10; 15)
+ EXPR_STMT@[15; 26)
+ LOOP_EXPR@[15; 26)
+ LABEL@[15; 18)
+ LIFETIME@[15; 17) "'a"
+ COLON@[17; 18)
+ WHITESPACE@[18; 19)
+ LOOP_KW@[19; 23)
+ WHITESPACE@[23; 24)
+ BLOCK_EXPR@[24; 26)
+ L_CURLY@[24; 25)
+ R_CURLY@[25; 26)
+ WHITESPACE@[26; 31)
+ EXPR_STMT@[31; 48)
+ WHILE_EXPR@[31; 48)
+ LABEL@[31; 34)
+ LIFETIME@[31; 33) "'b"
+ COLON@[33; 34)
+ WHITESPACE@[34; 35)
+ WHILE_KW@[35; 40)
+ WHITESPACE@[40; 41)
+ LITERAL@[41; 45)
+ TRUE_KW@[41; 45)
+ WHITESPACE@[45; 46)
+ BLOCK_EXPR@[46; 48)
+ L_CURLY@[46; 47)
+ R_CURLY@[47; 48)
+ WHITESPACE@[48; 53)
+ FOR_EXPR@[53; 71)
+ LABEL@[53; 56)
+ LIFETIME@[53; 55) "'c"
+ COLON@[55; 56)
+ WHITESPACE@[56; 57)
+ FOR_KW@[57; 60)
+ WHITESPACE@[60; 61)
+ BIND_PAT@[61; 62)
+ NAME@[61; 62)
+ IDENT@[61; 62) "x"
+ WHITESPACE@[62; 63)
+ IN_KW@[63; 65)
+ WHITESPACE@[65; 66)
+ TUPLE_EXPR@[66; 68)
+ L_PAREN@[66; 67)
+ R_PAREN@[67; 68)
+ WHITESPACE@[68; 69)
+ BLOCK_EXPR@[69; 71)
+ L_CURLY@[69; 70)
+ R_CURLY@[70; 71)
+ WHITESPACE@[71; 72)
+ R_CURLY@[72; 73)
+ WHITESPACE@[73; 74)
--
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