diff options
author | Aleksey Kladov <[email protected]> | 2019-01-31 18:43:54 +0000 |
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committer | Aleksey Kladov <[email protected]> | 2019-01-31 20:23:30 +0000 |
commit | a16f6bb27df1a9a9fcb506081bb30ccbf966e5c2 (patch) | |
tree | 7ec1a33ec57806979951fa5cefc3cc9a05b28987 /crates/ra_mbe/src/mbe_parser.rs | |
parent | 2d1f0b105d7995088fdf7a90e5e594b5555699c6 (diff) |
cleanup
Diffstat (limited to 'crates/ra_mbe/src/mbe_parser.rs')
-rw-r--r-- | crates/ra_mbe/src/mbe_parser.rs | 44 |
1 files changed, 23 insertions, 21 deletions
diff --git a/crates/ra_mbe/src/mbe_parser.rs b/crates/ra_mbe/src/mbe_parser.rs index a70ed1d52..a76ea84db 100644 --- a/crates/ra_mbe/src/mbe_parser.rs +++ b/crates/ra_mbe/src/mbe_parser.rs | |||
@@ -1,58 +1,59 @@ | |||
1 | use crate::{self as mbe, tt_cursor::TtCursor}; | 1 | use crate::tt_cursor::TtCursor; |
2 | 2 | ||
3 | /// This module parses a raw `tt::TokenStream` into macro-by-example token | 3 | /// This module parses a raw `tt::TokenStream` into macro-by-example token |
4 | /// stream. This is a *mostly* identify function, expect for handling of | 4 | /// stream. This is a *mostly* identify function, expect for handling of |
5 | /// `$var:tt_kind` and `$(repeat),*` constructs. | 5 | /// `$var:tt_kind` and `$(repeat),*` constructs. |
6 | 6 | ||
7 | pub fn parse(tt: &tt::Subtree) -> Option<mbe::MacroRules> { | 7 | pub fn parse(tt: &tt::Subtree) -> Option<crate::MacroRules> { |
8 | let mut parser = TtCursor::new(tt); | 8 | let mut parser = TtCursor::new(tt); |
9 | let mut rules = Vec::new(); | 9 | let mut rules = Vec::new(); |
10 | while !parser.is_eof() { | 10 | while !parser.is_eof() { |
11 | rules.push(parse_rule(&mut parser)?) | 11 | rules.push(parse_rule(&mut parser)?) |
12 | } | 12 | } |
13 | Some(mbe::MacroRules { rules }) | 13 | Some(crate::MacroRules { rules }) |
14 | } | 14 | } |
15 | 15 | ||
16 | fn parse_rule(p: &mut TtCursor) -> Option<mbe::Rule> { | 16 | fn parse_rule(p: &mut TtCursor) -> Option<crate::Rule> { |
17 | let lhs = parse_subtree(p.eat_subtree()?)?; | 17 | let lhs = parse_subtree(p.eat_subtree()?)?; |
18 | p.expect_char('=')?; | 18 | p.expect_char('=')?; |
19 | p.expect_char('>')?; | 19 | p.expect_char('>')?; |
20 | let rhs = parse_subtree(p.eat_subtree()?)?; | 20 | let mut rhs = parse_subtree(p.eat_subtree()?)?; |
21 | Some(mbe::Rule { lhs, rhs }) | 21 | rhs.delimiter = crate::Delimiter::None; |
22 | Some(crate::Rule { lhs, rhs }) | ||
22 | } | 23 | } |
23 | 24 | ||
24 | fn parse_subtree(tt: &tt::Subtree) -> Option<mbe::Subtree> { | 25 | fn parse_subtree(tt: &tt::Subtree) -> Option<crate::Subtree> { |
25 | let mut token_trees = Vec::new(); | 26 | let mut token_trees = Vec::new(); |
26 | let mut p = TtCursor::new(tt); | 27 | let mut p = TtCursor::new(tt); |
27 | while let Some(tt) = p.eat() { | 28 | while let Some(tt) = p.eat() { |
28 | let child: mbe::TokenTree = match tt { | 29 | let child: crate::TokenTree = match tt { |
29 | tt::TokenTree::Leaf(leaf) => match leaf { | 30 | tt::TokenTree::Leaf(leaf) => match leaf { |
30 | tt::Leaf::Punct(tt::Punct { char: '$', .. }) => { | 31 | tt::Leaf::Punct(tt::Punct { char: '$', .. }) => { |
31 | if p.at_ident().is_some() { | 32 | if p.at_ident().is_some() { |
32 | mbe::Leaf::from(parse_var(&mut p)?).into() | 33 | crate::Leaf::from(parse_var(&mut p)?).into() |
33 | } else { | 34 | } else { |
34 | parse_repeat(&mut p)?.into() | 35 | parse_repeat(&mut p)?.into() |
35 | } | 36 | } |
36 | } | 37 | } |
37 | tt::Leaf::Punct(punct) => mbe::Leaf::from(*punct).into(), | 38 | tt::Leaf::Punct(punct) => crate::Leaf::from(*punct).into(), |
38 | tt::Leaf::Ident(tt::Ident { text }) => { | 39 | tt::Leaf::Ident(tt::Ident { text }) => { |
39 | mbe::Leaf::from(mbe::Ident { text: text.clone() }).into() | 40 | crate::Leaf::from(crate::Ident { text: text.clone() }).into() |
40 | } | 41 | } |
41 | tt::Leaf::Literal(tt::Literal { text }) => { | 42 | tt::Leaf::Literal(tt::Literal { text }) => { |
42 | mbe::Leaf::from(mbe::Literal { text: text.clone() }).into() | 43 | crate::Leaf::from(crate::Literal { text: text.clone() }).into() |
43 | } | 44 | } |
44 | }, | 45 | }, |
45 | tt::TokenTree::Subtree(subtree) => parse_subtree(&subtree)?.into(), | 46 | tt::TokenTree::Subtree(subtree) => parse_subtree(&subtree)?.into(), |
46 | }; | 47 | }; |
47 | token_trees.push(child); | 48 | token_trees.push(child); |
48 | } | 49 | } |
49 | Some(mbe::Subtree { | 50 | Some(crate::Subtree { |
50 | token_trees, | 51 | token_trees, |
51 | delimiter: tt.delimiter, | 52 | delimiter: tt.delimiter, |
52 | }) | 53 | }) |
53 | } | 54 | } |
54 | 55 | ||
55 | fn parse_var(p: &mut TtCursor) -> Option<mbe::Var> { | 56 | fn parse_var(p: &mut TtCursor) -> Option<crate::Var> { |
56 | let ident = p.eat_ident().unwrap(); | 57 | let ident = p.eat_ident().unwrap(); |
57 | let text = ident.text.clone(); | 58 | let text = ident.text.clone(); |
58 | let kind = if p.at_char(':') { | 59 | let kind = if p.at_char(':') { |
@@ -66,12 +67,13 @@ fn parse_var(p: &mut TtCursor) -> Option<mbe::Var> { | |||
66 | } else { | 67 | } else { |
67 | None | 68 | None |
68 | }; | 69 | }; |
69 | Some(mbe::Var { text, kind }) | 70 | Some(crate::Var { text, kind }) |
70 | } | 71 | } |
71 | 72 | ||
72 | fn parse_repeat(p: &mut TtCursor) -> Option<mbe::Repeat> { | 73 | fn parse_repeat(p: &mut TtCursor) -> Option<crate::Repeat> { |
73 | let subtree = p.eat_subtree().unwrap(); | 74 | let subtree = p.eat_subtree().unwrap(); |
74 | let subtree = parse_subtree(subtree)?; | 75 | let mut subtree = parse_subtree(subtree)?; |
76 | subtree.delimiter = crate::Delimiter::None; | ||
75 | let sep = p.eat_punct()?; | 77 | let sep = p.eat_punct()?; |
76 | let (separator, rep) = match sep.char { | 78 | let (separator, rep) = match sep.char { |
77 | '*' | '+' | '?' => (None, sep.char), | 79 | '*' | '+' | '?' => (None, sep.char), |
@@ -79,13 +81,13 @@ fn parse_repeat(p: &mut TtCursor) -> Option<mbe::Repeat> { | |||
79 | }; | 81 | }; |
80 | 82 | ||
81 | let kind = match rep { | 83 | let kind = match rep { |
82 | '*' => mbe::RepeatKind::ZeroOrMore, | 84 | '*' => crate::RepeatKind::ZeroOrMore, |
83 | '+' => mbe::RepeatKind::OneOrMore, | 85 | '+' => crate::RepeatKind::OneOrMore, |
84 | '?' => mbe::RepeatKind::ZeroOrOne, | 86 | '?' => crate::RepeatKind::ZeroOrOne, |
85 | _ => return None, | 87 | _ => return None, |
86 | }; | 88 | }; |
87 | p.bump(); | 89 | p.bump(); |
88 | Some(mbe::Repeat { | 90 | Some(crate::Repeat { |
89 | subtree, | 91 | subtree, |
90 | kind, | 92 | kind, |
91 | separator, | 93 | separator, |