1use super::{Compiler, Symbol};
2use anyhow::Result;
3use dynamic::{Dynamic, Type};
4use parser::{BinaryOp, Expr, ExprKind, PatternKind, Span, Stmt, StmtKind};
5
6impl Compiler {
7 fn merge_return_type(span: Span, left: Option<Type>, right: Type) -> Result<Type> {
8 match left {
9 Some(left) if left == right => Ok(left),
10 Some(left) if left.is_void() || right.is_void() => Err(Self::semantic_error(span, format!("返回类型不一致: {:?} 和 {:?}", left, right))),
11 Some(left) => Ok(left + right),
12 None => Ok(right),
13 }
14 }
15
16 fn infer_return_type(&mut self, stmt: &Stmt) -> Result<Option<Type>> {
17 self.infer_returns(stmt, true).map(|(ty, _)| ty)
18 }
19
20 fn infer_returns(&mut self, stmt: &Stmt, tail: bool) -> Result<(Option<Type>, bool)> {
21 match &stmt.kind {
22 StmtKind::Return(Some(expr)) => Ok((Some(self.infer_expr(expr)?), true)),
23 StmtKind::Return(None) => Ok((Some(Type::Void), true)),
24 StmtKind::Block(stmts) => {
25 let mut ret = None;
26 for (idx, stmt) in stmts.iter().enumerate() {
27 let (ty, always_returns) = self.infer_returns(stmt, tail && idx == stmts.len().saturating_sub(1))?;
28 if let Some(ty) = ty {
29 ret = Some(Self::merge_return_type(stmt.span, ret, ty)?);
30 }
31 if always_returns {
32 return Ok((ret, true));
33 }
34 }
35 Ok((ret, false))
36 }
37 StmtKind::If { cond, then_body, else_body } => {
38 let cond_ty = self.infer_expr(cond)?;
39 if cond_ty != Type::Bool {
40 return Err(Self::semantic_error(cond.span, format!("条件表达式必须是布尔类型，实际是 {:?}", cond_ty)));
41 }
42 let (mut ret, then_returns) = self.infer_returns(then_body, tail)?;
43 let else_returns = if let Some(body) = else_body {
44 let (else_ty, else_returns) = self.infer_returns(body, tail)?;
45 if let Some(ty) = else_ty {
46 ret = Some(Self::merge_return_type(body.span, ret, ty)?);
47 }
48 else_returns
49 } else {
50 false
51 };
52 Ok((ret, then_returns && else_returns))
53 }
54 StmtKind::While { cond, body } => {
55 let cond_ty = self.infer_expr(cond)?;
56 if cond_ty != Type::Bool {
57 return Err(Self::semantic_error(cond.span, format!("条件表达式必须是布尔类型，实际是 {:?}", cond_ty)));
58 }
59 self.infer_returns(body, false).map(|(ty, _)| (ty, false))
60 }
61 StmtKind::Loop(body) => self.infer_returns(body, false),
62 StmtKind::For { pat, range, body } => {
63 if let PatternKind::Var { idx, .. } = &pat.kind {
64 let ty = self.infer_expr(range)?;
65 self.set_ty(*idx, ty);
66 } else if let PatternKind::Tuple(pats) = &pat.kind {
67 let ty = self.infer_expr(range)?;
68 assert!(ty.is_any());
69 for pat in pats {
70 if let Some(idx) = pat.var() {
71 self.set_ty(idx, Type::Any);
72 }
73 }
74 }
75 self.infer_returns(body, false).map(|(ty, _)| (ty, false))
76 }
77 StmtKind::Let { .. } => {
78 self.infer_stmt(stmt)?;
79 Ok((None, false))
80 }
81 StmtKind::Expr(expr, close) => {
82 let ty = self.infer_expr(expr)?;
83 Ok(if *close || !tail { (None, false) } else { (Some(ty), true) })
84 }
85 _ => {
86 self.infer_stmt(stmt)?;
87 Ok((None, false))
88 }
89 }
90 }
91
92 pub fn infer_expr(&mut self, expr: &Expr) -> Result<Type> {
93 match &expr.kind {
94 ExprKind::Value(Dynamic::Null) => Ok(Type::Any),
95 ExprKind::Value(v) => Ok(v.get_type()),
96 ExprKind::Var(idx) => {
97 let idx = self.top() + (*idx as usize);
98 if idx < self.tys.len() { self.symbols.get_type(&self.tys[idx]) } else { Ok(Type::Any) }
99 }
100 ExprKind::Id(id, _) => match self.symbols.get_symbol(*id)?.1 {
101 Symbol::Const { ty, .. } => Ok(ty.clone()),
102 Symbol::Static { ty, .. } => Ok(ty.clone()),
103 Symbol::Struct(ty, _) => Ok(ty.clone()),
104 Symbol::Fn { .. } => Ok(Type::Symbol { id: *id, params: Vec::new() }),
105 Symbol::Native(ty) => Ok(ty.clone()),
106 s => Err(Self::semantic_error(expr.span, format!("符号 {:?} 不是变量、常量、静态变量、结构体", s))),
107 },
108 ExprKind::AssocId { id, params } => Ok(Type::Symbol { id: *id, params: params.clone() }),
109 ExprKind::Unary { value, .. } => self.infer_expr(value.as_ref()),
110 ExprKind::Binary { left, op, right } => {
111 let assign_idx = if op.is_assign() { if let ExprKind::Var(idx) = &left.kind { Some(*idx) } else { None } } else { None };
112 let ty = if op.is_logic() {
113 let left_ty = self.infer_expr(left)?;
114 if matches!(op, BinaryOp::And | BinaryOp::Or) && left_ty.is_any() { Type::Any } else { Type::Bool }
115 } else if op == &BinaryOp::Idx {
116 let left_ty = self.infer_expr(left)?;
117 if let Type::Array(elem_ty, _) = left_ty {
118 (*elem_ty).clone()
119 } else if let Type::Vec(elem_ty, _) = left_ty {
120 (*elem_ty).clone()
121 } else {
122 let left_ty = self.symbols.get_type(&left_ty)?;
123 let right_ty = if right.is_value() || right.is_const() {
124 let right_value = if let ExprKind::Const(c) = &right.kind { self.consts[*c].clone() } else { right.clone().value()? };
125 if right_value.is_str() {
126 if left_ty.is_any() {
127 return Ok(Type::Any);
128 }
129 if let Ok(field) = self.symbols.get_field(&left_ty, right_value.as_str()) {
130 return if let Type::Fn { ret, .. } = field.1 { Ok(ret.as_ref().clone()) } else { Ok(field.1.clone()) };
131 }
132 } else if let Type::Struct { fields, .. } = &left_ty
133 && let Some(idx) = right_value.as_int()
134 {
135 return fields.get(idx as usize).map(|(_, ty)| ty.clone()).ok_or_else(|| Self::semantic_error(right.span, format!("结构字段索引越界 {}", idx)));
136 }
137 right_value.get_type()
138 } else {
139 self.infer_expr(right)?
140 };
141 if right_ty.is_int() || right_ty.is_uint() {
142 if left_ty.is_any() {
143 return Ok(Type::Any);
144 }
145 let (_, s) = self.symbols.get_field(&left_ty, "get_idx")?;
146 let fn_ty = self.symbols.get_type(&s)?;
147 return if let Type::Fn { ret, .. } = &fn_ty { Ok(ret.as_ref().clone()) } else { Ok(fn_ty) };
148 }
149 if left_ty.is_any() {
150 return Ok(Type::Any);
151 }
152 Type::Any
153 }
154 } else {
155 let right_ty = self.infer_expr(right)?;
156 if op == &BinaryOp::Assign { right_ty } else { self.infer_expr(left)? + right_ty }
157 };
158 assign_idx.map(|idx| self.set_ty(idx, ty.clone()));
159 Ok(ty)
160 }
161 ExprKind::Call { obj, params } => {
162 if let ExprKind::AssocId { id, params: generic_args } = &obj.kind {
163 let mut args = Vec::new();
164 for p in params {
165 args.push(self.infer_expr(p)?);
166 }
167 self.infer_fn_with_params(*id, &args, generic_args)
168 } else if let ExprKind::TypedMethod { obj: target, ty, name } = &obj.kind {
169 let base_name = match ty {
170 Type::Ident { name, .. } => name.clone(),
171 Type::Symbol { id, .. } => self.symbols.get_symbol(*id)?.0.clone(),
172 _ => return Ok(Type::Any),
173 };
174 let id = self.symbols.get_id(&format!("{}::{}", base_name, name))?;
175 let mut args = vec![self.infer_expr(target)?];
176 for p in params {
177 args.push(self.infer_expr(p)?);
178 }
179 self.infer_fn(id, &args)
180 } else if let ExprKind::Id(id, obj_expr) = &obj.kind {
181 let mut args: Vec<Type> = if let Some(obj) = obj_expr { vec![self.infer_expr(obj)?] } else { Vec::new() };
182 for p in params {
183 args.push(self.infer_expr(p)?);
184 }
185 self.infer_fn(*id, &args)
186 } else if obj.is_idx() {
187 let (target, _, method) = obj.clone().binary().unwrap();
188 let ty = self.infer_expr(&target)?;
189 if let Some(method) = self.get_value(&method) {
190 let method = method.as_str();
191 let fn_ty = match self.get_field(&ty, method) {
192 Ok((_, fn_ty)) => fn_ty,
193 Err(_) => {
194 let id = self.symbols.get_id(method)?;
195 if self.symbols.get_symbol(id)?.1.is_fn() {
196 Type::Symbol { id, params: Vec::new() }
197 } else {
198 return Err(Self::semantic_error(obj.span, format!("符号 {method} 不是函数")));
199 }
200 }
201 };
202 if let Type::Symbol { id, .. } = fn_ty {
203 let mut args = vec![ty];
204 for p in params {
205 args.push(self.infer_expr(p)?);
206 }
207 self.infer_fn(id, &args)
208 } else {
209 Ok(fn_ty)
210 }
211 } else {
212 Ok(Type::Any)
213 }
214 } else if let ExprKind::Var(idx) = &obj.kind {
215 let idx = self.top() + (*idx as usize);
216 if idx < self.tys.len()
217 && let Type::Symbol { id, .. } = self.tys[idx]
218 {
219 let mut args = Vec::new();
220 for p in params {
221 args.push(self.infer_expr(p)?);
222 }
223 self.infer_fn(id, &args)
224 } else {
225 Ok(Type::Any)
226 }
227 } else if obj.is_value() {
228 Ok(Type::Void)
229 } else {
230 Ok(Type::Any)
231 }
232 }
233 ExprKind::Typed { ty, .. } => Ok(ty.clone()),
234 ExprKind::Stmt(stmt) => self.infer_stmt(stmt),
235 ExprKind::Range { start, stop, .. } => {
236 let start_ty = self.infer_expr(start)?;
237 let stop_ty = self.infer_expr(stop)?;
238 Ok(if start_ty.is_any() {
239 stop_ty
240 } else if stop_ty.is_any() {
241 start_ty
242 } else {
243 stop_ty
244 })
245 }
246 _ => Ok(Type::Any),
247 }
248 }
249
250 fn get_fn_tys(&mut self, tys: &[Type], arg_tys: &[Type]) -> Result<Vec<Type>> {
251 let mut fn_tys = Vec::new();
252 for (i, ty) in tys.iter().enumerate() {
253 if !ty.is_any() {
254 fn_tys.push(ty.clone());
255 } else if let Some(arg_ty) = arg_tys.get(i) {
256 fn_tys.push(self.symbols.get_type(arg_ty)?);
257 } else {
258 fn_tys.push(Type::Any);
259 }
260 }
261 Ok(fn_tys)
262 }
263
264 pub fn infer_fn(&mut self, id: u32, arg_tys: &[Type]) -> Result<Type> {
265 self.infer_fn_with_params(id, arg_tys, &[])
266 }
267
268 pub fn infer_fn_with_params(&mut self, id: u32, arg_tys: &[Type], generic_args: &[Type]) -> Result<Type> {
269 let (name, s) = self.symbols.get_symbol(id).map(|(n, s)| (n.clone(), s.clone()))?;
270 if let Symbol::Fn { ty, args, generic_params, cap, body, .. } = s {
271 if let Type::Fn { tys, ret: _ } = ty {
272 let inferred_generic_args = if generic_args.is_empty() { crate::infer_generic_args_from_types(&generic_params, &tys, arg_tys) } else { generic_args.to_vec() };
273 let generic_args = if generic_params.is_empty() { &[] } else { inferred_generic_args.as_slice() };
274 let tys = if generic_params.is_empty() { tys } else { tys.iter().map(|ty| crate::substitute_type(ty, &generic_params, generic_args)).collect() };
275 let body = if generic_params.is_empty() { body.as_ref().clone() } else { crate::substitute_stmt(body.as_ref(), &generic_params, generic_args) };
276 let fn_tys = self.get_fn_tys(&tys, arg_tys)?;
277 let body = if generic_params.is_empty() {
278 body
279 } else {
280 let mut compile_tys = tys.clone();
281 let mut compile_cap = cap.clone();
282 let saved_state = self.take_local_state();
283 let compiled = self.compile_fn(&args, &mut compile_tys, body, &mut compile_cap);
284 self.restore_local_state(saved_state);
285 Stmt::new(StmtKind::Block(compiled?), Span::default())
286 };
287 if let Some(fns) = self.fns.get_mut(&id) {
288 for f in fns.iter() {
289 if f.0 == generic_args && f.1 == fn_tys {
290 return Ok(f.2.clone());
291 }
292 }
293 fns.push((generic_args.to_vec(), fn_tys.clone(), Type::Any));
294 } else {
295 self.fns.insert(id, vec![(generic_args.to_vec(), fn_tys.clone(), Type::Any)]);
296 }
297 let top = self.tys.len();
298 self.tys.append(&mut fn_tys.clone());
299 for c in cap.vars.iter() {
300 self.tys.push(self.tys[self.top() + *c].clone());
301 }
302 self.frames.push(top);
303 let ret_ty = self.infer_return_type(&body).map(|ty| ty.unwrap_or(Type::Void));
304 if let Some(top) = self.frames.pop() {
305 self.tys.truncate(top);
306 }
307 let ret_ty = match ret_ty {
308 Ok(ret_ty) => ret_ty,
309 Err(err) => {
310 log::error!("infer_fn {} failed: {:?}", name, err);
311 let should_remove = self
312 .fns
313 .get_mut(&id)
314 .map(|fns| {
315 fns.retain(|item| item.0 != generic_args || item.1 != fn_tys || item.2 != Type::Any);
316 fns.is_empty()
317 })
318 .unwrap_or(false);
319 if should_remove {
320 self.fns.remove(&id);
321 }
322 return Err(err);
323 }
324 };
325 self.fns.get_mut(&id).map(|f| {
326 f.iter_mut().find(|item| item.0 == generic_args && item.1 == fn_tys).map(|item| item.2 = ret_ty.clone());
327 });
328 Ok(ret_ty)
329 } else {
330 Ok(Type::Any)
331 }
332 } else if let Symbol::Native(f) = s {
333 if let Type::Fn { ret, .. } = f { Ok((*ret).clone()) } else { Ok(Type::Any) }
334 } else if matches!(s, Symbol::Null) {
335 Ok(Type::Any)
336 } else {
337 Err(Self::semantic_error(Span::default(), format!("符号 {:?} 不是函数", name)))
338 }
339 }
340
341 pub fn infer_stmt(&mut self, stmt: &Stmt) -> Result<Type> {
342 match &stmt.kind {
343 StmtKind::Expr(expr, close) => {
344 if !close {
345 self.infer_expr(expr)
346 } else {
347 self.infer_expr(expr)?;
348 Ok(Type::Void)
349 }
350 }
351 StmtKind::Return(expr) => {
352 if let Some(e) = expr {
353 self.infer_expr(e)
354 } else {
355 Ok(Type::Void)
356 }
357 }
358 StmtKind::Block(stmts) => {
359 for (idx, stmt) in stmts.iter().enumerate() {
360 let ty = self.infer_stmt(stmt)?;
361 if stmt.is_return() || idx == stmts.len() - 1 {
362 return Ok(ty);
363 }
364 }
365 Ok(Type::Void)
366 }
367 StmtKind::If { then_body, else_body, .. } => {
368 let then_ty = self.infer_stmt(then_body)?;
369 if let Some(e) = else_body {
370 let else_ty = self.infer_stmt(e)?;
371 if then_ty != else_ty {
372 log::info!("then 和 else 有不同类型 {:?} {:?}", then_ty, else_ty);
373 return Ok(if then_ty.is_any() { else_ty } else { then_ty });
374 }
375 }
376 if else_body.is_none() {
377 return Ok(Type::Void);
378 }
379 Ok(then_ty)
380 }
381 StmtKind::While { cond, body } => {
382 let cond_ty = self.infer_expr(cond)?;
383 if cond_ty != Type::Bool {
384 return Err(Self::semantic_error(cond.span, format!("条件表达式必须是布尔类型，实际是 {:?}", cond_ty)));
385 }
386 self.infer_stmt(body)
387 }
388 StmtKind::For { pat, range, body } => {
389 if let PatternKind::Var { idx, .. } = &pat.kind {
390 let ty = self.infer_expr(range)?;
391 self.set_ty(*idx, ty);
392 } else if let PatternKind::Tuple(pats) = &pat.kind {
393 let ty = self.infer_expr(range)?;
394 assert!(ty.is_any());
395 for pat in pats {
396 if let Some(idx) = pat.var() {
397 self.set_ty(idx, Type::Any);
398 }
399 }
400 }
401 self.infer_stmt(body)
402 }
403 StmtKind::Let { pat, value } => {
404 let expr_ty = if let StmtKind::Expr(expr, _) = &value.kind { self.infer_expr(expr)? } else { self.infer_stmt(value)? };
405 if let PatternKind::Ident { ty, .. } = &pat.kind {
406 let annotated_ty = self.symbols.get_type(ty)?;
407 if annotated_ty.is_any() {
408 self.add_ty(expr_ty);
409 } else {
410 self.add_ty(annotated_ty);
411 }
412 } else if let PatternKind::Var { idx, .. } = &pat.kind {
413 self.set_ty(*idx, expr_ty);
414 } else if matches!(pat.kind, PatternKind::Wildcard) {
415 self.add_ty(expr_ty);
416 }
417 Ok(Type::Void)
418 }
419 _ => Ok(Type::Void),
420 }
421 }
422}