1 // parse.h -- Go frontend parser. -*- C++ -*-
3 // Copyright 2009 The Go Authors. All rights reserved.
4 // Use of this source code is governed by a BSD-style
5 // license that can be found in the LICENSE file.
14 class Typed_identifier
;
15 class Typed_identifier_list
;
20 class Expression_list
;
21 class Struct_field_list
;
23 class Type_case_clauses
;
43 PRECEDENCE_INVALID
= -1,
44 PRECEDENCE_NORMAL
= 0,
52 // We use this when parsing the range clause of a for statement.
55 // Set to true if we found a range clause.
57 // The index expression.
59 // The value expression.
61 // The range expression.
65 : found(false), index(NULL
), value(NULL
), range(NULL
)
69 // We use this when parsing the statement at the start of a switch,
70 // in order to recognize type switches.
73 // Set to true if we find a type switch.
77 // The location of the variable.
83 : found(false), name(), location(Linemap::unknown_location()),
88 // A variable defined in an enclosing function referenced by the
93 Enclosing_var(Named_object
* var
, Named_object
* in_function
,
95 : var_(var
), in_function_(in_function
), index_(index
)
98 // We put these in a vector, so we need a default constructor.
100 : var_(NULL
), in_function_(NULL
), index_(-1U)
105 { return this->var_
; }
109 { return this->in_function_
; }
113 { return this->index_
; }
116 // The variable which is being referred to.
118 // The function where the variable is defined.
119 Named_object
* in_function_
;
120 // The index of the field in this function's closure struct for
125 // We store Enclosing_var entries in a set, so we need a comparator.
126 struct Enclosing_var_comparison
129 operator()(const Enclosing_var
&, const Enclosing_var
&) const;
132 // A set of Enclosing_var entries.
133 typedef std::set
<Enclosing_var
, Enclosing_var_comparison
> Enclosing_vars
;
135 // Used to detect duplicate parameter/result names.
136 typedef std::map
<std::string
, const Typed_identifier
*> Names
;
138 // Peek at the current token from the lexer.
142 // Consume the current token, return the next one.
146 // Push a token back on the input stream.
148 unget_token(const Token
&);
150 // The location of the current token.
154 // For break and continue we keep a stack of statements with
155 // associated labels (if any). The top of the stack is used for a
156 // break or continue statement with no label.
157 typedef std::vector
<std::pair
<Statement
*, Label
*> > Bc_stack
;
159 // Parser nonterminals.
160 void identifier_list(Typed_identifier_list
*);
161 Expression_list
* expression_list(Expression
*, bool may_be_sink
,
162 bool may_be_composite_lit
);
163 bool qualified_ident(std::string
*, Named_object
**);
165 bool type_may_start_here();
166 Type
* type_name(bool issue_error
);
167 Type
* array_type(bool may_use_ellipsis
);
170 void field_decl(Struct_field_list
*);
171 Type
* pointer_type();
172 Type
* channel_type();
173 void check_signature_names(const Typed_identifier_list
*, Names
*);
174 Function_type
* signature(Typed_identifier
*, Location
);
175 bool parameters(Typed_identifier_list
**, bool* is_varargs
);
176 Typed_identifier_list
* parameter_list(bool* is_varargs
);
177 void parameter_decl(bool, Typed_identifier_list
*, bool*, bool*, bool*);
178 bool result(Typed_identifier_list
**);
180 Type
* interface_type(bool record
);
181 void method_spec(Typed_identifier_list
*);
183 bool declaration_may_start_here();
184 void decl(void (Parse::*)(void*, unsigned int), void*, unsigned int pragmas
);
185 void list(void (Parse::*)(void*, unsigned int), void*, bool);
187 void const_spec(int, Type
**, Expression_list
**);
188 void type_decl(unsigned int pragmas
);
189 void type_spec(void*, unsigned int pragmas
);
191 void var_spec(void*, unsigned int pragmas
);
192 void init_vars(const Typed_identifier_list
*, Type
*, Expression_list
*,
193 bool is_coloneq
, Location
);
194 bool init_vars_from_call(const Typed_identifier_list
*, Type
*, Expression
*,
195 bool is_coloneq
, Location
);
196 bool init_vars_from_map(const Typed_identifier_list
*, Type
*, Expression
*,
197 bool is_coloneq
, Location
);
198 bool init_vars_from_receive(const Typed_identifier_list
*, Type
*,
199 Expression
*, bool is_coloneq
, Location
);
200 bool init_vars_from_type_guard(const Typed_identifier_list
*, Type
*,
201 Expression
*, bool is_coloneq
,
203 Named_object
* init_var(const Typed_identifier
&, Type
*, Expression
*,
204 bool is_coloneq
, bool type_from_init
, bool* is_new
,
205 Expression_list
* vars
, Expression_list
* vals
);
206 Named_object
* create_dummy_global(Type
*, Expression
*, Location
);
207 void finish_init_vars(Expression_list
* vars
, Expression_list
* vals
,
209 void simple_var_decl_or_assignment(const std::string
&, Location
,
210 bool may_be_composite_lit
,
211 Range_clause
*, Type_switch
*);
212 void function_decl(unsigned int pragmas
);
213 Typed_identifier
* receiver();
214 Expression
* operand(bool may_be_sink
, bool *is_parenthesized
);
215 Expression
* enclosing_var_reference(Named_object
*, Named_object
*,
216 bool may_be_sink
, Location
);
217 Expression
* composite_lit(Type
*, int depth
, Location
);
218 Expression
* function_lit();
219 Expression
* create_closure(Named_object
* function
, Enclosing_vars
*,
221 Expression
* primary_expr(bool may_be_sink
, bool may_be_composite_lit
,
222 bool* is_type_switch
, bool* is_parenthesized
);
223 Expression
* selector(Expression
*, bool* is_type_switch
);
224 Expression
* index(Expression
*);
225 Expression
* call(Expression
*);
226 Expression
* expression(Precedence
, bool may_be_sink
,
227 bool may_be_composite_lit
, bool* is_type_switch
,
228 bool *is_parenthesized
);
229 bool expression_may_start_here();
230 Expression
* unary_expr(bool may_be_sink
, bool may_be_composite_lit
,
231 bool* is_type_switch
, bool* is_parenthesized
);
232 Type
* reassociate_chan_direction(Channel_type
*, Location
);
233 Expression
* qualified_expr(Expression
*, Location
);
234 Expression
* id_to_expression(const std::string
&, Location
, bool, bool);
235 void statement(Label
*);
236 bool statement_may_start_here();
237 void labeled_stmt(const std::string
&, Location
);
238 Expression
* simple_stat(bool, bool*, Range_clause
*, Type_switch
*);
239 bool simple_stat_may_start_here();
240 void statement_list();
241 bool statement_list_may_start_here();
242 void expression_stat(Expression
*);
243 void send_stmt(Expression
*, bool may_be_composite_lit
);
244 void inc_dec_stat(Expression
*);
245 void assignment(Expression
*, bool may_be_composite_lit
, Range_clause
*);
246 void tuple_assignment(Expression_list
*, bool may_be_composite_lit
,
249 void go_or_defer_stat();
252 void switch_stat(Label
*);
253 Statement
* expr_switch_body(Label
*, Expression
*, Location
);
254 void expr_case_clause(Case_clauses
*, bool* saw_default
);
255 Expression_list
* expr_switch_case(bool*);
256 Statement
* type_switch_body(Label
*, const Type_switch
&, Location
);
257 void type_case_clause(const std::string
&, Expression
*, Type_case_clauses
*,
258 bool* saw_default
, std::vector
<Named_object
*>*);
259 void type_switch_case(std::vector
<Type
*>*, bool*);
260 void select_stat(Label
*);
261 void comm_clause(Select_clauses
*, bool* saw_default
);
262 bool comm_case(bool*, Expression
**, Expression
**, Expression
**,
263 std::string
*, std::string
*, bool*);
264 bool send_or_recv_stmt(bool*, Expression
**, Expression
**, Expression
**,
265 std::string
*, std::string
*);
266 void for_stat(Label
*);
267 void for_clause(Expression
**, Block
**);
268 void range_clause_decl(const Typed_identifier_list
*, Range_clause
*);
269 void range_clause_expr(const Expression_list
*, Range_clause
*);
270 void push_break_statement(Statement
*, Label
*);
271 void push_continue_statement(Statement
*, Label
*);
272 void pop_break_statement();
273 void pop_continue_statement();
274 Statement
* find_bc_statement(const Bc_stack
*, const std::string
&);
276 void continue_stat();
278 void package_clause();
280 void import_spec(void*, unsigned int pragmas
);
282 // Skip past an error looking for a semicolon or OP. Return true if
283 // all is well, false if we found EOF.
285 skip_past_error(Operator op
);
287 // Verify that an expression is not a sink, and return either the
288 // expression or an error.
290 verify_not_sink(Expression
*);
292 // Return the statement associated with a label in a Bc_stack, or
295 find_bc_statement(const Bc_stack
*, const std::string
&) const;
297 // Mark a variable as used.
299 mark_var_used(Named_object
*);
301 // The lexer output we are parsing.
303 // The current token.
305 // A token pushed back on the input stream.
307 // Whether unget_token_ is valid.
308 bool unget_token_valid_
;
309 // Whether the function we are parsing had errors in the signature.
310 bool is_erroneous_function_
;
311 // The code we are generating.
313 // A stack of statements for which break may be used.
314 Bc_stack
* break_stack_
;
315 // A stack of statements for which continue may be used.
316 Bc_stack
* continue_stack_
;
317 // References from the local function to variables defined in
318 // enclosing functions.
319 Enclosing_vars enclosing_vars_
;
323 #endif // !defined(GO_PARSE_H)