diff options
Diffstat (limited to 'crates/libsyntax2/src/grammar/expressions')
-rw-r--r-- | crates/libsyntax2/src/grammar/expressions/atom.rs | 400 | ||||
-rw-r--r-- | crates/libsyntax2/src/grammar/expressions/mod.rs | 450 |
2 files changed, 0 insertions, 850 deletions
diff --git a/crates/libsyntax2/src/grammar/expressions/atom.rs b/crates/libsyntax2/src/grammar/expressions/atom.rs deleted file mode 100644 index f01df56bc..000000000 --- a/crates/libsyntax2/src/grammar/expressions/atom.rs +++ /dev/null | |||
@@ -1,400 +0,0 @@ | |||
1 | use super::*; | ||
2 | |||
3 | // test expr_literals | ||
4 | // fn foo() { | ||
5 | // let _ = true; | ||
6 | // let _ = false; | ||
7 | // let _ = 1; | ||
8 | // let _ = 2.0; | ||
9 | // let _ = b'a'; | ||
10 | // let _ = 'b'; | ||
11 | // let _ = "c"; | ||
12 | // let _ = r"d"; | ||
13 | // let _ = b"e"; | ||
14 | // let _ = br"f"; | ||
15 | // } | ||
16 | pub(crate) const LITERAL_FIRST: TokenSet = | ||
17 | token_set![TRUE_KW, FALSE_KW, INT_NUMBER, FLOAT_NUMBER, BYTE, CHAR, | ||
18 | STRING, RAW_STRING, BYTE_STRING, RAW_BYTE_STRING]; | ||
19 | |||
20 | pub(crate) fn literal(p: &mut Parser) -> Option<CompletedMarker> { | ||
21 | if !p.at_ts(LITERAL_FIRST) { | ||
22 | return None; | ||
23 | } | ||
24 | let m = p.start(); | ||
25 | p.bump(); | ||
26 | Some(m.complete(p, LITERAL)) | ||
27 | } | ||
28 | |||
29 | pub(super) const ATOM_EXPR_FIRST: TokenSet = | ||
30 | token_set_union![ | ||
31 | LITERAL_FIRST, | ||
32 | token_set![L_CURLY, L_PAREN, L_BRACK, PIPE, MOVE_KW, IF_KW, WHILE_KW, MATCH_KW, UNSAFE_KW, | ||
33 | RETURN_KW, IDENT, SELF_KW, SUPER_KW, COLONCOLON, BREAK_KW, CONTINUE_KW, LIFETIME ], | ||
34 | ]; | ||
35 | |||
36 | const EXPR_RECOVERY_SET: TokenSet = | ||
37 | token_set![LET_KW]; | ||
38 | |||
39 | pub(super) fn atom_expr(p: &mut Parser, r: Restrictions) -> Option<CompletedMarker> { | ||
40 | match literal(p) { | ||
41 | Some(m) => return Some(m), | ||
42 | None => (), | ||
43 | } | ||
44 | if paths::is_path_start(p) || p.at(L_ANGLE) { | ||
45 | return Some(path_expr(p, r)); | ||
46 | } | ||
47 | let la = p.nth(1); | ||
48 | let done = match p.current() { | ||
49 | L_PAREN => tuple_expr(p), | ||
50 | L_BRACK => array_expr(p), | ||
51 | PIPE => lambda_expr(p), | ||
52 | MOVE_KW if la == PIPE => lambda_expr(p), | ||
53 | IF_KW => if_expr(p), | ||
54 | |||
55 | LOOP_KW => loop_expr(p, None), | ||
56 | FOR_KW => for_expr(p, None), | ||
57 | WHILE_KW => while_expr(p, None), | ||
58 | LIFETIME if la == COLON => { | ||
59 | let m = p.start(); | ||
60 | label(p); | ||
61 | match p.current() { | ||
62 | LOOP_KW => loop_expr(p, Some(m)), | ||
63 | FOR_KW => for_expr(p, Some(m)), | ||
64 | WHILE_KW => while_expr(p, Some(m)), | ||
65 | L_CURLY => block_expr(p, Some(m)), | ||
66 | _ => { | ||
67 | // test misplaced_label_err | ||
68 | // fn main() { | ||
69 | // 'loop: impl | ||
70 | // } | ||
71 | p.error("expected a loop"); | ||
72 | m.complete(p, ERROR); | ||
73 | return None; | ||
74 | } | ||
75 | } | ||
76 | } | ||
77 | |||
78 | MATCH_KW => match_expr(p), | ||
79 | UNSAFE_KW if la == L_CURLY => { | ||
80 | let m = p.start(); | ||
81 | p.bump(); | ||
82 | block_expr(p, Some(m)) | ||
83 | }, | ||
84 | L_CURLY => block_expr(p, None), | ||
85 | RETURN_KW => return_expr(p), | ||
86 | CONTINUE_KW => continue_expr(p), | ||
87 | BREAK_KW => break_expr(p), | ||
88 | _ => { | ||
89 | p.err_recover("expected expression", EXPR_RECOVERY_SET); | ||
90 | return None; | ||
91 | } | ||
92 | }; | ||
93 | Some(done) | ||
94 | } | ||
95 | |||
96 | // test tuple_expr | ||
97 | // fn foo() { | ||
98 | // (); | ||
99 | // (1); | ||
100 | // (1,); | ||
101 | // } | ||
102 | fn tuple_expr(p: &mut Parser) -> CompletedMarker { | ||
103 | assert!(p.at(L_PAREN)); | ||
104 | let m = p.start(); | ||
105 | p.expect(L_PAREN); | ||
106 | |||
107 | let mut saw_comma = false; | ||
108 | let mut saw_expr = false; | ||
109 | while !p.at(EOF) && !p.at(R_PAREN) { | ||
110 | saw_expr = true; | ||
111 | if !p.at_ts(EXPR_FIRST) { | ||
112 | p.error("expected expression"); | ||
113 | break; | ||
114 | } | ||
115 | expr(p); | ||
116 | if !p.at(R_PAREN) { | ||
117 | saw_comma = true; | ||
118 | p.expect(COMMA); | ||
119 | } | ||
120 | } | ||
121 | p.expect(R_PAREN); | ||
122 | m.complete(p, if saw_expr && !saw_comma { PAREN_EXPR } else { TUPLE_EXPR }) | ||
123 | } | ||
124 | |||
125 | // test array_expr | ||
126 | // fn foo() { | ||
127 | // []; | ||
128 | // [1]; | ||
129 | // [1, 2,]; | ||
130 | // [1; 2]; | ||
131 | // } | ||
132 | fn array_expr(p: &mut Parser) -> CompletedMarker { | ||
133 | assert!(p.at(L_BRACK)); | ||
134 | let m = p.start(); | ||
135 | p.bump(); | ||
136 | if p.eat(R_BRACK) { | ||
137 | return m.complete(p, ARRAY_EXPR); | ||
138 | } | ||
139 | expr(p); | ||
140 | if p.eat(SEMI) { | ||
141 | expr(p); | ||
142 | p.expect(R_BRACK); | ||
143 | return m.complete(p, ARRAY_EXPR); | ||
144 | } | ||
145 | while !p.at(EOF) && !p.at(R_BRACK) { | ||
146 | p.expect(COMMA); | ||
147 | if p.at(R_BRACK) { | ||
148 | break; | ||
149 | } | ||
150 | if !p.at_ts(EXPR_FIRST) { | ||
151 | p.error("expected expression"); | ||
152 | break; | ||
153 | } | ||
154 | expr(p); | ||
155 | } | ||
156 | p.expect(R_BRACK); | ||
157 | m.complete(p, ARRAY_EXPR) | ||
158 | } | ||
159 | |||
160 | // test lambda_expr | ||
161 | // fn foo() { | ||
162 | // || (); | ||
163 | // || -> i32 { 92 }; | ||
164 | // |x| x; | ||
165 | // move |x: i32,| x; | ||
166 | // } | ||
167 | fn lambda_expr(p: &mut Parser) -> CompletedMarker { | ||
168 | assert!(p.at(PIPE) || (p.at(MOVE_KW) && p.nth(1) == PIPE)); | ||
169 | let m = p.start(); | ||
170 | p.eat(MOVE_KW); | ||
171 | params::param_list_opt_types(p); | ||
172 | if opt_fn_ret_type(p) { | ||
173 | if !p.at(L_CURLY) { | ||
174 | p.error("expected `{`"); | ||
175 | } | ||
176 | } | ||
177 | expr(p); | ||
178 | m.complete(p, LAMBDA_EXPR) | ||
179 | } | ||
180 | |||
181 | // test if_expr | ||
182 | // fn foo() { | ||
183 | // if true {}; | ||
184 | // if true {} else {}; | ||
185 | // if true {} else if false {} else {}; | ||
186 | // if S {}; | ||
187 | // } | ||
188 | fn if_expr(p: &mut Parser) -> CompletedMarker { | ||
189 | assert!(p.at(IF_KW)); | ||
190 | let m = p.start(); | ||
191 | p.bump(); | ||
192 | cond(p); | ||
193 | block(p); | ||
194 | if p.at(ELSE_KW) { | ||
195 | p.bump(); | ||
196 | if p.at(IF_KW) { | ||
197 | if_expr(p); | ||
198 | } else { | ||
199 | block(p); | ||
200 | } | ||
201 | } | ||
202 | m.complete(p, IF_EXPR) | ||
203 | } | ||
204 | |||
205 | // test label | ||
206 | // fn foo() { | ||
207 | // 'a: loop {} | ||
208 | // 'b: while true {} | ||
209 | // 'c: for x in () {} | ||
210 | // } | ||
211 | fn label(p: &mut Parser) { | ||
212 | assert!(p.at(LIFETIME) && p.nth(1) == COLON); | ||
213 | let m = p.start(); | ||
214 | p.bump(); | ||
215 | p.bump(); | ||
216 | m.complete(p, LABEL); | ||
217 | } | ||
218 | |||
219 | // test loop_expr | ||
220 | // fn foo() { | ||
221 | // loop {}; | ||
222 | // } | ||
223 | fn loop_expr(p: &mut Parser, m: Option<Marker>) -> CompletedMarker { | ||
224 | assert!(p.at(LOOP_KW)); | ||
225 | let m = m.unwrap_or_else(|| p.start()); | ||
226 | p.bump(); | ||
227 | block(p); | ||
228 | m.complete(p, LOOP_EXPR) | ||
229 | } | ||
230 | |||
231 | // test while_expr | ||
232 | // fn foo() { | ||
233 | // while true {}; | ||
234 | // while let Some(x) = it.next() {}; | ||
235 | // } | ||
236 | fn while_expr(p: &mut Parser, m: Option<Marker>) -> CompletedMarker { | ||
237 | assert!(p.at(WHILE_KW)); | ||
238 | let m = m.unwrap_or_else(|| p.start()); | ||
239 | p.bump(); | ||
240 | cond(p); | ||
241 | block(p); | ||
242 | m.complete(p, WHILE_EXPR) | ||
243 | } | ||
244 | |||
245 | // test for_expr | ||
246 | // fn foo() { | ||
247 | // for x in [] {}; | ||
248 | // } | ||
249 | fn for_expr(p: &mut Parser, m: Option<Marker>) -> CompletedMarker { | ||
250 | assert!(p.at(FOR_KW)); | ||
251 | let m = m.unwrap_or_else(|| p.start()); | ||
252 | p.bump(); | ||
253 | patterns::pattern(p); | ||
254 | p.expect(IN_KW); | ||
255 | expr_no_struct(p); | ||
256 | block(p); | ||
257 | m.complete(p, FOR_EXPR) | ||
258 | } | ||
259 | |||
260 | // test cond | ||
261 | // fn foo() { if let Some(_) = None {} } | ||
262 | fn cond(p: &mut Parser) { | ||
263 | let m = p.start(); | ||
264 | if p.eat(LET_KW) { | ||
265 | patterns::pattern(p); | ||
266 | p.expect(EQ); | ||
267 | } | ||
268 | expr_no_struct(p); | ||
269 | m.complete(p, CONDITION); | ||
270 | } | ||
271 | |||
272 | // test match_expr | ||
273 | // fn foo() { | ||
274 | // match () { }; | ||
275 | // match S {}; | ||
276 | // } | ||
277 | fn match_expr(p: &mut Parser) -> CompletedMarker { | ||
278 | assert!(p.at(MATCH_KW)); | ||
279 | let m = p.start(); | ||
280 | p.bump(); | ||
281 | expr_no_struct(p); | ||
282 | if p.at(L_CURLY) { | ||
283 | match_arm_list(p); | ||
284 | } else { | ||
285 | p.error("expected `{`") | ||
286 | } | ||
287 | m.complete(p, MATCH_EXPR) | ||
288 | } | ||
289 | |||
290 | pub(crate) fn match_arm_list(p: &mut Parser) { | ||
291 | assert!(p.at(L_CURLY)); | ||
292 | let m = p.start(); | ||
293 | p.eat(L_CURLY); | ||
294 | while !p.at(EOF) && !p.at(R_CURLY) { | ||
295 | if p.at(L_CURLY) { | ||
296 | error_block(p, "expected match arm"); | ||
297 | continue; | ||
298 | } | ||
299 | // test match_arms_commas | ||
300 | // fn foo() { | ||
301 | // match () { | ||
302 | // _ => (), | ||
303 | // _ => {} | ||
304 | // _ => () | ||
305 | // } | ||
306 | // } | ||
307 | if match_arm(p).is_block() { | ||
308 | p.eat(COMMA); | ||
309 | } else if !p.at(R_CURLY) { | ||
310 | p.expect(COMMA); | ||
311 | } | ||
312 | } | ||
313 | p.expect(R_CURLY); | ||
314 | m.complete(p, MATCH_ARM_LIST); | ||
315 | } | ||
316 | |||
317 | // test match_arm | ||
318 | // fn foo() { | ||
319 | // match () { | ||
320 | // _ => (), | ||
321 | // X | Y if Z => (), | ||
322 | // }; | ||
323 | // } | ||
324 | fn match_arm(p: &mut Parser) -> BlockLike { | ||
325 | let m = p.start(); | ||
326 | patterns::pattern_r(p, TokenSet::EMPTY); | ||
327 | while p.eat(PIPE) { | ||
328 | patterns::pattern(p); | ||
329 | } | ||
330 | if p.eat(IF_KW) { | ||
331 | expr_no_struct(p); | ||
332 | } | ||
333 | p.expect(FAT_ARROW); | ||
334 | let ret = expr_stmt(p); | ||
335 | m.complete(p, MATCH_ARM); | ||
336 | ret | ||
337 | } | ||
338 | |||
339 | // test block_expr | ||
340 | // fn foo() { | ||
341 | // {}; | ||
342 | // unsafe {}; | ||
343 | // 'label: {}; | ||
344 | // } | ||
345 | fn block_expr(p: &mut Parser, m: Option<Marker>) -> CompletedMarker { | ||
346 | assert!(p.at(L_CURLY)); | ||
347 | let m = m.unwrap_or_else(|| p.start()); | ||
348 | block(p); | ||
349 | m.complete(p, BLOCK_EXPR) | ||
350 | } | ||
351 | |||
352 | // test return_expr | ||
353 | // fn foo() { | ||
354 | // return; | ||
355 | // return 92; | ||
356 | // } | ||
357 | fn return_expr(p: &mut Parser) -> CompletedMarker { | ||
358 | assert!(p.at(RETURN_KW)); | ||
359 | let m = p.start(); | ||
360 | p.bump(); | ||
361 | if p.at_ts(EXPR_FIRST) { | ||
362 | expr(p); | ||
363 | } | ||
364 | m.complete(p, RETURN_EXPR) | ||
365 | } | ||
366 | |||
367 | // test continue_expr | ||
368 | // fn foo() { | ||
369 | // loop { | ||
370 | // continue; | ||
371 | // continue 'l; | ||
372 | // } | ||
373 | // } | ||
374 | fn continue_expr(p: &mut Parser) -> CompletedMarker { | ||
375 | assert!(p.at(CONTINUE_KW)); | ||
376 | let m = p.start(); | ||
377 | p.bump(); | ||
378 | p.eat(LIFETIME); | ||
379 | m.complete(p, CONTINUE_EXPR) | ||
380 | } | ||
381 | |||
382 | // test break_expr | ||
383 | // fn foo() { | ||
384 | // loop { | ||
385 | // break; | ||
386 | // break 'l; | ||
387 | // break 92; | ||
388 | // break 'l 92; | ||
389 | // } | ||
390 | // } | ||
391 | fn break_expr(p: &mut Parser) -> CompletedMarker { | ||
392 | assert!(p.at(BREAK_KW)); | ||
393 | let m = p.start(); | ||
394 | p.bump(); | ||
395 | p.eat(LIFETIME); | ||
396 | if p.at_ts(EXPR_FIRST) { | ||
397 | expr(p); | ||
398 | } | ||
399 | m.complete(p, BREAK_EXPR) | ||
400 | } | ||
diff --git a/crates/libsyntax2/src/grammar/expressions/mod.rs b/crates/libsyntax2/src/grammar/expressions/mod.rs deleted file mode 100644 index 20e0fa328..000000000 --- a/crates/libsyntax2/src/grammar/expressions/mod.rs +++ /dev/null | |||
@@ -1,450 +0,0 @@ | |||
1 | mod atom; | ||
2 | |||
3 | use super::*; | ||
4 | pub(super) use self::atom::{literal, LITERAL_FIRST}; | ||
5 | pub(crate) use self::atom::match_arm_list; | ||
6 | |||
7 | const EXPR_FIRST: TokenSet = LHS_FIRST; | ||
8 | |||
9 | pub(super) fn expr(p: &mut Parser) -> BlockLike { | ||
10 | let r = Restrictions { forbid_structs: false, prefer_stmt: false }; | ||
11 | expr_bp(p, r, 1) | ||
12 | } | ||
13 | |||
14 | pub(super) fn expr_stmt(p: &mut Parser) -> BlockLike { | ||
15 | let r = Restrictions { forbid_structs: false, prefer_stmt: true }; | ||
16 | expr_bp(p, r, 1) | ||
17 | } | ||
18 | |||
19 | fn expr_no_struct(p: &mut Parser) { | ||
20 | let r = Restrictions { forbid_structs: true, prefer_stmt: false }; | ||
21 | expr_bp(p, r, 1); | ||
22 | } | ||
23 | |||
24 | // test block | ||
25 | // fn a() {} | ||
26 | // fn b() { let _ = 1; } | ||
27 | // fn c() { 1; 2; } | ||
28 | // fn d() { 1; 2 } | ||
29 | pub(crate) fn block(p: &mut Parser) { | ||
30 | if !p.at(L_CURLY) { | ||
31 | p.error("expected a block"); | ||
32 | return; | ||
33 | } | ||
34 | let m = p.start(); | ||
35 | p.bump(); | ||
36 | while !p.at(EOF) && !p.at(R_CURLY) { | ||
37 | match p.current() { | ||
38 | LET_KW => let_stmt(p), | ||
39 | _ => { | ||
40 | // test block_items | ||
41 | // fn a() { fn b() {} } | ||
42 | let m = p.start(); | ||
43 | match items::maybe_item(p, items::ItemFlavor::Mod) { | ||
44 | items::MaybeItem::Item(kind) => { | ||
45 | m.complete(p, kind); | ||
46 | } | ||
47 | items::MaybeItem::Modifiers => { | ||
48 | m.abandon(p); | ||
49 | p.error("expected an item"); | ||
50 | } | ||
51 | // test pub_expr | ||
52 | // fn foo() { pub 92; } //FIXME | ||
53 | items::MaybeItem::None => { | ||
54 | let is_blocklike = expressions::expr_stmt(p) == BlockLike::Block; | ||
55 | if p.at(R_CURLY) { | ||
56 | m.abandon(p); | ||
57 | } else { | ||
58 | if is_blocklike { | ||
59 | p.eat(SEMI); | ||
60 | } else { | ||
61 | p.expect(SEMI); | ||
62 | } | ||
63 | m.complete(p, EXPR_STMT); | ||
64 | } | ||
65 | } | ||
66 | } | ||
67 | } | ||
68 | } | ||
69 | } | ||
70 | p.expect(R_CURLY); | ||
71 | m.complete(p, BLOCK); | ||
72 | |||
73 | // test let_stmt; | ||
74 | // fn foo() { | ||
75 | // let a; | ||
76 | // let b: i32; | ||
77 | // let c = 92; | ||
78 | // let d: i32 = 92; | ||
79 | // } | ||
80 | fn let_stmt(p: &mut Parser) { | ||
81 | assert!(p.at(LET_KW)); | ||
82 | let m = p.start(); | ||
83 | p.bump(); | ||
84 | patterns::pattern(p); | ||
85 | if p.at(COLON) { | ||
86 | types::ascription(p); | ||
87 | } | ||
88 | if p.eat(EQ) { | ||
89 | expressions::expr(p); | ||
90 | } | ||
91 | p.expect(SEMI); | ||
92 | m.complete(p, LET_STMT); | ||
93 | } | ||
94 | } | ||
95 | |||
96 | #[derive(Clone, Copy)] | ||
97 | struct Restrictions { | ||
98 | forbid_structs: bool, | ||
99 | prefer_stmt: bool, | ||
100 | } | ||
101 | |||
102 | enum Op { | ||
103 | Simple, | ||
104 | Composite(SyntaxKind, u8), | ||
105 | } | ||
106 | |||
107 | fn current_op(p: &Parser) -> (u8, Op) { | ||
108 | if let Some(t) = p.next3() { | ||
109 | match t { | ||
110 | (L_ANGLE, L_ANGLE, EQ) => | ||
111 | return (1, Op::Composite(SHLEQ, 3)), | ||
112 | (R_ANGLE, R_ANGLE, EQ) => | ||
113 | return (1, Op::Composite(SHREQ, 3)), | ||
114 | _ => (), | ||
115 | } | ||
116 | } | ||
117 | |||
118 | if let Some(t) = p.next2() { | ||
119 | match t { | ||
120 | (PLUS, EQ) => return (1, Op::Composite(PLUSEQ, 2)), | ||
121 | (MINUS, EQ) => return (1, Op::Composite(MINUSEQ, 2)), | ||
122 | (STAR, EQ) => return (1, Op::Composite(STAREQ, 2)), | ||
123 | (SLASH, EQ) => return (1, Op::Composite(SLASHEQ, 2)), | ||
124 | (PIPE, EQ) => return (1, Op::Composite(PIPEEQ, 2)), | ||
125 | (AMP, EQ) => return (1, Op::Composite(AMPEQ, 2)), | ||
126 | (CARET, EQ) => return (1, Op::Composite(CARETEQ, 2)), | ||
127 | (PIPE, PIPE) => return (3, Op::Composite(PIPEPIPE, 2)), | ||
128 | (AMP, AMP) => return (4, Op::Composite(AMPAMP, 2)), | ||
129 | (L_ANGLE, EQ) => return (5, Op::Composite(LTEQ, 2)), | ||
130 | (R_ANGLE, EQ) => return (5, Op::Composite(GTEQ, 2)), | ||
131 | (L_ANGLE, L_ANGLE) => return (9, Op::Composite(SHL, 2)), | ||
132 | (R_ANGLE, R_ANGLE) => return (9, Op::Composite(SHR, 2)), | ||
133 | _ => (), | ||
134 | } | ||
135 | } | ||
136 | |||
137 | let bp = match p.current() { | ||
138 | EQ => 1, | ||
139 | DOTDOT => 2, | ||
140 | EQEQ | NEQ | L_ANGLE | R_ANGLE => 5, | ||
141 | PIPE => 6, | ||
142 | CARET => 7, | ||
143 | AMP => 8, | ||
144 | MINUS | PLUS => 10, | ||
145 | STAR | SLASH | PERCENT => 11, | ||
146 | _ => 0, | ||
147 | }; | ||
148 | (bp, Op::Simple) | ||
149 | } | ||
150 | |||
151 | // Parses expression with binding power of at least bp. | ||
152 | fn expr_bp(p: &mut Parser, r: Restrictions, bp: u8) -> BlockLike { | ||
153 | let mut lhs = match lhs(p, r) { | ||
154 | Some(lhs) => { | ||
155 | // test stmt_bin_expr_ambiguity | ||
156 | // fn foo() { | ||
157 | // let _ = {1} & 2; | ||
158 | // {1} &2; | ||
159 | // } | ||
160 | if r.prefer_stmt && is_block(lhs.kind()) { | ||
161 | return BlockLike::Block; | ||
162 | } | ||
163 | lhs | ||
164 | } | ||
165 | None => return BlockLike::NotBlock, | ||
166 | }; | ||
167 | |||
168 | loop { | ||
169 | let is_range = p.current() == DOTDOT; | ||
170 | let (op_bp, op) = current_op(p); | ||
171 | if op_bp < bp { | ||
172 | break; | ||
173 | } | ||
174 | let m = lhs.precede(p); | ||
175 | match op { | ||
176 | Op::Simple => p.bump(), | ||
177 | Op::Composite(kind, n) => { | ||
178 | p.bump_compound(kind, n); | ||
179 | } | ||
180 | } | ||
181 | expr_bp(p, r, op_bp + 1); | ||
182 | lhs = m.complete(p, if is_range { RANGE_EXPR } else { BIN_EXPR }); | ||
183 | } | ||
184 | BlockLike::NotBlock | ||
185 | } | ||
186 | |||
187 | // test no_semi_after_block | ||
188 | // fn foo() { | ||
189 | // if true {} | ||
190 | // loop {} | ||
191 | // match () {} | ||
192 | // while true {} | ||
193 | // for _ in () {} | ||
194 | // {} | ||
195 | // {} | ||
196 | // } | ||
197 | fn is_block(kind: SyntaxKind) -> bool { | ||
198 | match kind { | ||
199 | IF_EXPR | WHILE_EXPR | FOR_EXPR | LOOP_EXPR | MATCH_EXPR | BLOCK_EXPR => true, | ||
200 | _ => false, | ||
201 | } | ||
202 | } | ||
203 | |||
204 | const LHS_FIRST: TokenSet = | ||
205 | token_set_union![ | ||
206 | token_set![AMP, STAR, EXCL, DOTDOT, MINUS], | ||
207 | atom::ATOM_EXPR_FIRST, | ||
208 | ]; | ||
209 | |||
210 | fn lhs(p: &mut Parser, r: Restrictions) -> Option<CompletedMarker> { | ||
211 | let m; | ||
212 | let kind = match p.current() { | ||
213 | // test ref_expr | ||
214 | // fn foo() { | ||
215 | // let _ = &1; | ||
216 | // let _ = &mut &f(); | ||
217 | // } | ||
218 | AMP => { | ||
219 | m = p.start(); | ||
220 | p.bump(); | ||
221 | p.eat(MUT_KW); | ||
222 | REF_EXPR | ||
223 | } | ||
224 | // test unary_expr | ||
225 | // fn foo() { | ||
226 | // **&1; | ||
227 | // !!true; | ||
228 | // --1; | ||
229 | // } | ||
230 | STAR | EXCL | MINUS => { | ||
231 | m = p.start(); | ||
232 | p.bump(); | ||
233 | PREFIX_EXPR | ||
234 | } | ||
235 | // test full_range_expr | ||
236 | // fn foo() { xs[..]; } | ||
237 | DOTDOT => { | ||
238 | m = p.start(); | ||
239 | p.bump(); | ||
240 | if p.at_ts(EXPR_FIRST) { | ||
241 | expr_bp(p, r, 2); | ||
242 | } | ||
243 | return Some(m.complete(p, RANGE_EXPR)); | ||
244 | } | ||
245 | _ => { | ||
246 | let lhs = atom::atom_expr(p, r)?; | ||
247 | return Some(postfix_expr(p, r, lhs)); | ||
248 | } | ||
249 | }; | ||
250 | expr_bp(p, r, 255); | ||
251 | Some(m.complete(p, kind)) | ||
252 | } | ||
253 | |||
254 | fn postfix_expr(p: &mut Parser, r: Restrictions, mut lhs: CompletedMarker) -> CompletedMarker { | ||
255 | let mut allow_calls = !r.prefer_stmt || !is_block(lhs.kind()); | ||
256 | loop { | ||
257 | lhs = match p.current() { | ||
258 | // test stmt_postfix_expr_ambiguity | ||
259 | // fn foo() { | ||
260 | // match () { | ||
261 | // _ => {} | ||
262 | // () => {} | ||
263 | // [] => {} | ||
264 | // } | ||
265 | // } | ||
266 | L_PAREN if allow_calls => call_expr(p, lhs), | ||
267 | L_BRACK if allow_calls => index_expr(p, lhs), | ||
268 | DOT if p.nth(1) == IDENT => if p.nth(2) == L_PAREN || p.nth(2) == COLONCOLON { | ||
269 | method_call_expr(p, lhs) | ||
270 | } else { | ||
271 | field_expr(p, lhs) | ||
272 | }, | ||
273 | DOT if p.nth(1) == INT_NUMBER => field_expr(p, lhs), | ||
274 | // test postfix_range | ||
275 | // fn foo() { let x = 1..; } | ||
276 | DOTDOT if !EXPR_FIRST.contains(p.nth(1)) => { | ||
277 | let m = lhs.precede(p); | ||
278 | p.bump(); | ||
279 | m.complete(p, RANGE_EXPR) | ||
280 | } | ||
281 | QUESTION => try_expr(p, lhs), | ||
282 | AS_KW => cast_expr(p, lhs), | ||
283 | _ => break, | ||
284 | }; | ||
285 | allow_calls = true | ||
286 | } | ||
287 | lhs | ||
288 | } | ||
289 | |||
290 | // test call_expr | ||
291 | // fn foo() { | ||
292 | // let _ = f(); | ||
293 | // let _ = f()(1)(1, 2,); | ||
294 | // } | ||
295 | fn call_expr(p: &mut Parser, lhs: CompletedMarker) -> CompletedMarker { | ||
296 | assert!(p.at(L_PAREN)); | ||
297 | let m = lhs.precede(p); | ||
298 | arg_list(p); | ||
299 | m.complete(p, CALL_EXPR) | ||
300 | } | ||
301 | |||
302 | // test index_expr | ||
303 | // fn foo() { | ||
304 | // x[1][2]; | ||
305 | // } | ||
306 | fn index_expr(p: &mut Parser, lhs: CompletedMarker) -> CompletedMarker { | ||
307 | assert!(p.at(L_BRACK)); | ||
308 | let m = lhs.precede(p); | ||
309 | p.bump(); | ||
310 | expr(p); | ||
311 | p.expect(R_BRACK); | ||
312 | m.complete(p, INDEX_EXPR) | ||
313 | } | ||
314 | |||
315 | // test method_call_expr | ||
316 | // fn foo() { | ||
317 | // x.foo(); | ||
318 | // y.bar::<T>(1, 2,); | ||
319 | // } | ||
320 | fn method_call_expr(p: &mut Parser, lhs: CompletedMarker) -> CompletedMarker { | ||
321 | assert!( | ||
322 | p.at(DOT) && p.nth(1) == IDENT | ||
323 | && (p.nth(2) == L_PAREN || p.nth(2) == COLONCOLON) | ||
324 | ); | ||
325 | let m = lhs.precede(p); | ||
326 | p.bump(); | ||
327 | name_ref(p); | ||
328 | type_args::opt_type_arg_list(p, true); | ||
329 | if p.at(L_PAREN) { | ||
330 | arg_list(p); | ||
331 | } | ||
332 | m.complete(p, METHOD_CALL_EXPR) | ||
333 | } | ||
334 | |||
335 | // test field_expr | ||
336 | // fn foo() { | ||
337 | // x.foo; | ||
338 | // x.0.bar; | ||
339 | // } | ||
340 | fn field_expr(p: &mut Parser, lhs: CompletedMarker) -> CompletedMarker { | ||
341 | assert!(p.at(DOT) && (p.nth(1) == IDENT || p.nth(1) == INT_NUMBER)); | ||
342 | let m = lhs.precede(p); | ||
343 | p.bump(); | ||
344 | if p.at(IDENT) { | ||
345 | name_ref(p) | ||
346 | } else { | ||
347 | p.bump() | ||
348 | } | ||
349 | m.complete(p, FIELD_EXPR) | ||
350 | } | ||
351 | |||
352 | // test try_expr | ||
353 | // fn foo() { | ||
354 | // x?; | ||
355 | // } | ||
356 | fn try_expr(p: &mut Parser, lhs: CompletedMarker) -> CompletedMarker { | ||
357 | assert!(p.at(QUESTION)); | ||
358 | let m = lhs.precede(p); | ||
359 | p.bump(); | ||
360 | m.complete(p, TRY_EXPR) | ||
361 | } | ||
362 | |||
363 | // test cast_expr | ||
364 | // fn foo() { | ||
365 | // 82 as i32; | ||
366 | // } | ||
367 | fn cast_expr(p: &mut Parser, lhs: CompletedMarker) -> CompletedMarker { | ||
368 | assert!(p.at(AS_KW)); | ||
369 | let m = lhs.precede(p); | ||
370 | p.bump(); | ||
371 | types::type_(p); | ||
372 | m.complete(p, CAST_EXPR) | ||
373 | } | ||
374 | |||
375 | fn arg_list(p: &mut Parser) { | ||
376 | assert!(p.at(L_PAREN)); | ||
377 | let m = p.start(); | ||
378 | p.bump(); | ||
379 | while !p.at(R_PAREN) && !p.at(EOF) { | ||
380 | if !p.at_ts(EXPR_FIRST) { | ||
381 | p.error("expected expression"); | ||
382 | break; | ||
383 | } | ||
384 | expr(p); | ||
385 | if !p.at(R_PAREN) && !p.expect(COMMA) { | ||
386 | break; | ||
387 | } | ||
388 | } | ||
389 | p.eat(R_PAREN); | ||
390 | m.complete(p, ARG_LIST); | ||
391 | } | ||
392 | |||
393 | // test path_expr | ||
394 | // fn foo() { | ||
395 | // let _ = a; | ||
396 | // let _ = a::b; | ||
397 | // let _ = ::a::<b>; | ||
398 | // let _ = format!(); | ||
399 | // } | ||
400 | fn path_expr(p: &mut Parser, r: Restrictions) -> CompletedMarker { | ||
401 | assert!(paths::is_path_start(p) || p.at(L_ANGLE)); | ||
402 | let m = p.start(); | ||
403 | paths::expr_path(p); | ||
404 | match p.current() { | ||
405 | L_CURLY if !r.forbid_structs => { | ||
406 | named_field_list(p); | ||
407 | m.complete(p, STRUCT_LIT) | ||
408 | } | ||
409 | EXCL => { | ||
410 | items::macro_call_after_excl(p); | ||
411 | m.complete(p, MACRO_CALL) | ||
412 | } | ||
413 | _ => m.complete(p, PATH_EXPR) | ||
414 | } | ||
415 | } | ||
416 | |||
417 | // test struct_lit | ||
418 | // fn foo() { | ||
419 | // S {}; | ||
420 | // S { x, y: 32, }; | ||
421 | // S { x, y: 32, ..Default::default() }; | ||
422 | // } | ||
423 | pub(crate) fn named_field_list(p: &mut Parser) { | ||
424 | assert!(p.at(L_CURLY)); | ||
425 | let m = p.start(); | ||
426 | p.bump(); | ||
427 | while !p.at(EOF) && !p.at(R_CURLY) { | ||
428 | match p.current() { | ||
429 | IDENT => { | ||
430 | let m = p.start(); | ||
431 | name_ref(p); | ||
432 | if p.eat(COLON) { | ||
433 | expr(p); | ||
434 | } | ||
435 | m.complete(p, NAMED_FIELD); | ||
436 | } | ||
437 | DOTDOT => { | ||
438 | p.bump(); | ||
439 | expr(p); | ||
440 | } | ||
441 | L_CURLY => error_block(p, "expected a field"), | ||
442 | _ => p.err_and_bump("expected identifier"), | ||
443 | } | ||
444 | if !p.at(R_CURLY) { | ||
445 | p.expect(COMMA); | ||
446 | } | ||
447 | } | ||
448 | p.expect(R_CURLY); | ||
449 | m.complete(p, NAMED_FIELD_LIST); | ||
450 | } | ||