source: src/Parser/lex.ll@ 2890212

ADT arm-eh ast-experimental enum forall-pointer-decay jacob/cs343-translation new-ast new-ast-unique-expr pthread-emulation qualifiedEnum
Last change on this file since 2890212 was 553772b, checked in by Peter A. Buhr <pabuhr@…>, 6 years ago

add new type constructor "generator" with temporary coroutine semantics

  • Property mode set to 100644
File size: 19.1 KB
Line 
1/*
2 * Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
3 *
4 * The contents of this file are covered under the licence agreement in the
5 * file "LICENCE" distributed with Cforall.
6 *
7 * lex.ll --
8 *
9 * Author : Peter A. Buhr
10 * Created On : Sat Sep 22 08:58:10 2001
11 * Last Modified By : Peter A. Buhr
12 * Last Modified On : Wed May 15 21:25:27 2019
13 * Update Count : 708
14 */
15
16%option yylineno
17%option noyywrap
18%option nounput
19
20%{
21// The lexer assumes the program has been preprocessed by cpp. Hence, all user level preprocessor directive have been
22// performed and removed from the source. The only exceptions are preprocessor directives passed to the compiler (e.g.,
23// line-number directives) and C/C++ style comments, which are ignored.
24
25//**************************** Includes and Defines ****************************
26
27// trigger before each matching rule's action
28#define YY_USER_ACTION \
29 yylloc.first_line = yylineno; \
30 yylloc.first_column = column; \
31 column += yyleng; \
32 yylloc.last_column = column; \
33 yylloc.last_line = yylineno; \
34 yylloc.filename = yyfilename ? yyfilename : "";
35unsigned int column = 0; // position of the end of the last token parsed
36
37#include <string>
38#include <cstdio> // FILENAME_MAX
39using namespace std;
40
41#include "config.h" // configure info
42#include "ParseNode.h"
43#include "TypedefTable.h"
44
45char *yyfilename;
46string *strtext; // accumulate parts of character and string constant value
47
48#define RETURN_LOCN(x) yylval.tok.loc.file = yyfilename; yylval.tok.loc.line = yylineno; return( x )
49#define RETURN_VAL(x) yylval.tok.str = new string( yytext ); RETURN_LOCN( x )
50#define RETURN_CHAR(x) yylval.tok.str = nullptr; RETURN_LOCN( x )
51#define RETURN_STR(x) yylval.tok.str = strtext; RETURN_LOCN( x )
52
53#define WHITE_RETURN(x) // do nothing
54#define NEWLINE_RETURN() column = 0; WHITE_RETURN( '\n' )
55#define ASCIIOP_RETURN() RETURN_CHAR( (int)yytext[0] ) // single character operator
56#define NAMEDOP_RETURN(x) RETURN_CHAR( x ) // multichar operator, with a name
57#define NUMERIC_RETURN(x) rm_underscore(); RETURN_VAL( x ) // numeric constant
58#define KEYWORD_RETURN(x) RETURN_CHAR( x ) // keyword
59#define QKEYWORD_RETURN(x) RETURN_VAL(x); // quasi-keyword
60#define IDENTIFIER_RETURN() RETURN_VAL( typedefTable.isKind( yytext ) )
61#define ATTRIBUTE_RETURN() RETURN_VAL( ATTR_IDENTIFIER )
62
63#ifdef HAVE_KEYWORDS_FLOATXX // GCC >= 7 => keyword, otherwise typedef
64#define FLOATXX(v) KEYWORD_RETURN(v);
65#else
66#define FLOATXX(v) IDENTIFIER_RETURN();
67#endif // HAVE_KEYWORDS_FLOATXX
68
69void rm_underscore() {
70 // SKULLDUGGERY: remove underscores (ok to shorten?)
71 yyleng = 0;
72 for ( int i = 0; yytext[i] != '\0'; i += 1 ) { // copying non-underscore characters to front of string
73 if ( yytext[i] != '_' ) {
74 yytext[yyleng] = yytext[i];
75 yyleng += 1;
76 } // if
77 } // for
78 yytext[yyleng] = '\0';
79} // rm_underscore
80
81// Stop warning due to incorrectly generated flex code.
82#pragma GCC diagnostic ignored "-Wsign-compare"
83%}
84
85binary [0-1]
86octal [0-7]
87nonzero [1-9]
88decimal [0-9]
89hex [0-9a-fA-F]
90universal_char "\\"((u"_"?{hex_quad})|(U"_"?{hex_quad}{2}))
91
92 // identifier, GCC: $ in identifier
93identifier ([a-zA-Z_$]|{universal_char})([0-9a-zA-Z_$]|{universal_char})*
94
95 // attribute identifier, GCC: $ in identifier
96attr_identifier "@"{identifier}
97
98 // numeric constants, CFA: '_' in constant
99hex_quad {hex}("_"?{hex}){3}
100size_opt (8|16|32|64|128)?
101 // CFA: explicit l8/l16/l32/l64/l128, char 'hh', short 'h', int 'n'
102length ("ll"|"LL"|[lL]{size_opt})|("hh"|"HH"|[hHnN])
103 // CFA: size_t 'z', pointer 'p', which define a sign and length
104integer_suffix_opt ("_"?(([uU]({length}?[iI]?)|([iI]{length}))|([iI]({length}?[uU]?)|([uU]{length}))|({length}([iI]?[uU]?)|([uU][iI]))|[zZ]|[pP]))?
105
106octal_digits ({octal})|({octal}({octal}|"_")*{octal})
107octal_prefix "0""_"?
108octal_constant (("0")|({octal_prefix}{octal_digits})){integer_suffix_opt}
109
110nonzero_digits ({nonzero})|({nonzero}({decimal}|"_")*{decimal})
111decimal_constant {nonzero_digits}{integer_suffix_opt}
112
113binary_digits ({binary})|({binary}({binary}|"_")*{binary})
114binary_prefix "0"[bB]"_"?
115binary_constant {binary_prefix}{binary_digits}{integer_suffix_opt}
116
117hex_digits ({hex})|({hex}({hex}|"_")*{hex})
118hex_prefix "0"[xX]"_"?
119hex_constant {hex_prefix}{hex_digits}{integer_suffix_opt}
120
121 // GCC: D (double) and iI (imaginary) suffixes, and DL (long double)
122exponent "_"?[eE]"_"?[+-]?{decimal_digits}
123floating_size 16|32|32x|64|64x|80|128|128x
124floating_length ([fFdDlLwWqQ]|[fF]{floating_size})
125floating_suffix ({floating_length}?[iI]?)|([iI]{floating_length})
126floating_suffix_opt ("_"?({floating_suffix}|"DL"))?
127decimal_digits ({decimal})|({decimal}({decimal}|"_")*{decimal})
128floating_decimal {decimal_digits}"."{exponent}?{floating_suffix_opt}
129floating_fraction "."{decimal_digits}{exponent}?{floating_suffix_opt}
130floating_constant ({decimal_digits}{exponent}{floating_suffix_opt})|({decimal_digits}{floating_fraction})
131
132binary_exponent "_"?[pP]"_"?[+-]?{decimal_digits}
133hex_floating_suffix_opt ("_"?({floating_suffix}))?
134hex_floating_fraction ({hex_digits}?"."{hex_digits})|({hex_digits}".")
135hex_floating_constant {hex_prefix}(({hex_floating_fraction}{binary_exponent})|({hex_digits}{binary_exponent})){hex_floating_suffix_opt}
136
137 // character escape sequence, GCC: \e => esc character
138simple_escape "\\"[abefnrtv'"?\\]
139 // ' stop editor highlighting
140octal_escape "\\"{octal}("_"?{octal}){0,2}
141hex_escape "\\""x""_"?{hex_digits}
142escape_seq {simple_escape}|{octal_escape}|{hex_escape}|{universal_char}
143cwide_prefix "L"|"U"|"u"
144swide_prefix {cwide_prefix}|"u8"
145
146 // display/white-space characters
147h_tab [\011]
148form_feed [\014]
149v_tab [\013]
150c_return [\015]
151h_white [ ]|{h_tab}
152
153 // overloadable operators
154op_unary_only "~"|"!"
155op_unary_binary "+"|"-"|"*"
156op_unary_pre_post "++"|"--"
157op_unary {op_unary_only}|{op_unary_binary}|{op_unary_pre_post}
158
159op_binary_only "/"|"%"|"\\"|"^"|"&"|"|"|"<"|">"|"="|"=="|"!="|"<<"|">>"|"<="|">="|"+="|"-="|"*="|"/="|"%="|"\\="|"&="|"|="|"^="|"<<="|">>="
160op_binary_over {op_unary_binary}|{op_binary_only}
161 // op_binary_not_over "?"|"->"|"."|"&&"|"||"|"@="
162 // operator {op_unary_pre_post}|{op_binary_over}|{op_binary_not_over}
163
164%x COMMENT
165%x BKQUOTE
166%x QUOTE
167%x STRING
168
169%%
170 /* line directives */
171^{h_white}*"#"{h_white}*[0-9]+{h_white}*["][^"\n]+["].*"\n" {
172 /* " stop editor highlighting */
173 static char filename[FILENAME_MAX]; // temporarily store current source-file name
174 char *end_num;
175 char *begin_string, *end_string;
176 long lineno, length;
177 lineno = strtol( yytext + 1, &end_num, 0 );
178 begin_string = strchr( end_num, '"' );
179 if ( begin_string ) { // file name ?
180 end_string = strchr( begin_string + 1, '"' ); // look for ending delimiter
181 assert( end_string ); // closing quote ?
182 length = end_string - begin_string - 1; // file-name length without quotes or sentinel
183 assert( length < FILENAME_MAX ); // room for sentinel ?
184 memcpy( &filename, begin_string + 1, length ); // copy file name from yytext
185 filename[ length ] = '\0'; // terminate string with sentinel
186 //cout << "file " << filename << " line " << lineno << endl;
187 yylineno = lineno;
188 yyfilename = filename;
189 } // if
190}
191
192 /* preprocessor-style directives */
193^{h_white}*"#"[^\n]*"\n" { RETURN_VAL( DIRECTIVE ); }
194
195 /* ignore C style comments (ALSO HANDLED BY CPP) */
196"/*" { BEGIN COMMENT; }
197<COMMENT>.|\n ;
198<COMMENT>"*/" { BEGIN 0; }
199
200 /* ignore C++ style comments (ALSO HANDLED BY CPP) */
201"//"[^\n]*"\n" ;
202
203 /* ignore whitespace */
204{h_white}+ { WHITE_RETURN(' '); }
205({v_tab}|{c_return}|{form_feed})+ { WHITE_RETURN(' '); }
206({h_white}|{v_tab}|{c_return}|{form_feed})*"\n" { NEWLINE_RETURN(); }
207
208 /* keywords */
209_Alignas { KEYWORD_RETURN(ALIGNAS); } // C11
210_Alignof { KEYWORD_RETURN(ALIGNOF); } // C11
211__alignof { KEYWORD_RETURN(ALIGNOF); } // GCC
212__alignof__ { KEYWORD_RETURN(ALIGNOF); } // GCC
213asm { KEYWORD_RETURN(ASM); }
214__asm { KEYWORD_RETURN(ASM); } // GCC
215__asm__ { KEYWORD_RETURN(ASM); } // GCC
216_Atomic { KEYWORD_RETURN(ATOMIC); } // C11
217__attribute { KEYWORD_RETURN(ATTRIBUTE); } // GCC
218__attribute__ { KEYWORD_RETURN(ATTRIBUTE); } // GCC
219auto { KEYWORD_RETURN(AUTO); }
220basetypeof { KEYWORD_RETURN(BASETYPEOF); } // CFA
221_Bool { KEYWORD_RETURN(BOOL); } // C99
222break { KEYWORD_RETURN(BREAK); }
223case { KEYWORD_RETURN(CASE); }
224catch { KEYWORD_RETURN(CATCH); } // CFA
225catchResume { KEYWORD_RETURN(CATCHRESUME); } // CFA
226char { KEYWORD_RETURN(CHAR); }
227choose { KEYWORD_RETURN(CHOOSE); } // CFA
228coerce { KEYWORD_RETURN(COERCE); } // CFA
229_Complex { KEYWORD_RETURN(COMPLEX); } // C99
230__complex { KEYWORD_RETURN(COMPLEX); } // GCC
231__complex__ { KEYWORD_RETURN(COMPLEX); } // GCC
232const { KEYWORD_RETURN(CONST); }
233__const { KEYWORD_RETURN(CONST); } // GCC
234__const__ { KEYWORD_RETURN(CONST); } // GCC
235continue { KEYWORD_RETURN(CONTINUE); }
236coroutine { KEYWORD_RETURN(COROUTINE); } // CFA
237default { KEYWORD_RETURN(DEFAULT); }
238disable { KEYWORD_RETURN(DISABLE); } // CFA
239do { KEYWORD_RETURN(DO); }
240double { KEYWORD_RETURN(DOUBLE); }
241dtype { KEYWORD_RETURN(DTYPE); } // CFA
242else { KEYWORD_RETURN(ELSE); }
243enable { KEYWORD_RETURN(ENABLE); } // CFA
244enum { KEYWORD_RETURN(ENUM); }
245__extension__ { KEYWORD_RETURN(EXTENSION); } // GCC
246exception { KEYWORD_RETURN(EXCEPTION); } // CFA
247extern { KEYWORD_RETURN(EXTERN); }
248fallthrough { KEYWORD_RETURN(FALLTHROUGH); } // CFA
249fallthru { KEYWORD_RETURN(FALLTHRU); } // CFA
250finally { KEYWORD_RETURN(FINALLY); } // CFA
251float { KEYWORD_RETURN(FLOAT); }
252__float80 { KEYWORD_RETURN(uuFLOAT80); } // GCC
253float80 { KEYWORD_RETURN(uuFLOAT80); } // GCC
254__float128 { KEYWORD_RETURN(uuFLOAT128); } // GCC
255float128 { KEYWORD_RETURN(uuFLOAT128); } // GCC
256_Float16 { FLOATXX(uFLOAT16); } // GCC
257_Float32 { FLOATXX(uFLOAT32); } // GCC
258_Float32x { FLOATXX(uFLOAT32X); } // GCC
259_Float64 { FLOATXX(uFLOAT64); } // GCC
260_Float64x { FLOATXX(uFLOAT64X); } // GCC
261_Float128 { FLOATXX(uFLOAT128); } // GCC
262_Float128x { FLOATXX(uFLOAT128); } // GCC
263for { KEYWORD_RETURN(FOR); }
264forall { KEYWORD_RETURN(FORALL); } // CFA
265fortran { KEYWORD_RETURN(FORTRAN); }
266ftype { KEYWORD_RETURN(FTYPE); } // CFA
267generator { KEYWORD_RETURN(GENERATOR); } // CFA
268_Generic { KEYWORD_RETURN(GENERIC); } // C11
269goto { KEYWORD_RETURN(GOTO); }
270if { KEYWORD_RETURN(IF); }
271_Imaginary { KEYWORD_RETURN(IMAGINARY); } // C99
272__imag { KEYWORD_RETURN(IMAGINARY); } // GCC
273__imag__ { KEYWORD_RETURN(IMAGINARY); } // GCC
274inline { KEYWORD_RETURN(INLINE); } // C99
275__inline { KEYWORD_RETURN(INLINE); } // GCC
276__inline__ { KEYWORD_RETURN(INLINE); } // GCC
277int { KEYWORD_RETURN(INT); }
278__int128 { KEYWORD_RETURN(INT128); } // GCC
279int128 { KEYWORD_RETURN(INT128); } // GCC
280__label__ { KEYWORD_RETURN(LABEL); } // GCC
281long { KEYWORD_RETURN(LONG); }
282monitor { KEYWORD_RETURN(MONITOR); } // CFA
283mutex { KEYWORD_RETURN(MUTEX); } // CFA
284_Noreturn { KEYWORD_RETURN(NORETURN); } // C11
285__builtin_offsetof { KEYWORD_RETURN(OFFSETOF); } // GCC
286one_t { NUMERIC_RETURN(ONE_T); } // CFA
287or { QKEYWORD_RETURN(WOR); } // CFA
288otype { KEYWORD_RETURN(OTYPE); } // CFA
289register { KEYWORD_RETURN(REGISTER); }
290restrict { KEYWORD_RETURN(RESTRICT); } // C99
291__restrict { KEYWORD_RETURN(RESTRICT); } // GCC
292__restrict__ { KEYWORD_RETURN(RESTRICT); } // GCC
293return { KEYWORD_RETURN(RETURN); }
294short { KEYWORD_RETURN(SHORT); }
295signed { KEYWORD_RETURN(SIGNED); }
296__signed { KEYWORD_RETURN(SIGNED); } // GCC
297__signed__ { KEYWORD_RETURN(SIGNED); } // GCC
298sizeof { KEYWORD_RETURN(SIZEOF); }
299static { KEYWORD_RETURN(STATIC); }
300_Static_assert { KEYWORD_RETURN(STATICASSERT); } // C11
301struct { KEYWORD_RETURN(STRUCT); }
302switch { KEYWORD_RETURN(SWITCH); }
303thread { KEYWORD_RETURN(THREAD); } // C11
304_Thread_local { KEYWORD_RETURN(THREADLOCAL); } // C11
305throw { KEYWORD_RETURN(THROW); } // CFA
306throwResume { KEYWORD_RETURN(THROWRESUME); } // CFA
307timeout { QKEYWORD_RETURN(TIMEOUT); } // CFA
308trait { KEYWORD_RETURN(TRAIT); } // CFA
309try { KEYWORD_RETURN(TRY); } // CFA
310ttype { KEYWORD_RETURN(TTYPE); } // CFA
311typedef { KEYWORD_RETURN(TYPEDEF); }
312typeof { KEYWORD_RETURN(TYPEOF); } // GCC
313__typeof { KEYWORD_RETURN(TYPEOF); } // GCC
314__typeof__ { KEYWORD_RETURN(TYPEOF); } // GCC
315union { KEYWORD_RETURN(UNION); }
316unsigned { KEYWORD_RETURN(UNSIGNED); }
317__builtin_va_list { KEYWORD_RETURN(VALIST); } // GCC
318virtual { KEYWORD_RETURN(VIRTUAL); } // CFA
319void { KEYWORD_RETURN(VOID); }
320volatile { KEYWORD_RETURN(VOLATILE); }
321__volatile { KEYWORD_RETURN(VOLATILE); } // GCC
322__volatile__ { KEYWORD_RETURN(VOLATILE); } // GCC
323waitfor { KEYWORD_RETURN(WAITFOR); }
324when { KEYWORD_RETURN(WHEN); }
325while { KEYWORD_RETURN(WHILE); }
326with { KEYWORD_RETURN(WITH); } // CFA
327zero_t { NUMERIC_RETURN(ZERO_T); } // CFA
328
329 /* identifier */
330{identifier} { IDENTIFIER_RETURN(); }
331"`"{identifier}"`" { // CFA
332 yytext[yyleng - 1] = '\0'; yytext += 1; // SKULLDUGGERY: remove backquotes (ok to shorten?)
333 IDENTIFIER_RETURN();
334}
335{attr_identifier} { ATTRIBUTE_RETURN(); }
336
337 /* numeric constants */
338{binary_constant} { NUMERIC_RETURN(INTEGERconstant); }
339{octal_constant} { NUMERIC_RETURN(INTEGERconstant); }
340{decimal_constant} { NUMERIC_RETURN(INTEGERconstant); }
341{hex_constant} { NUMERIC_RETURN(INTEGERconstant); }
342{floating_decimal} { NUMERIC_RETURN(FLOATING_DECIMALconstant); } // must appear before floating_constant
343{floating_fraction} { NUMERIC_RETURN(FLOATING_FRACTIONconstant); } // must appear before floating_constant
344{floating_constant} { NUMERIC_RETURN(FLOATINGconstant); }
345{hex_floating_constant} { NUMERIC_RETURN(FLOATINGconstant); }
346
347 /* character constant, allows empty value */
348({cwide_prefix}[_]?)?['] { BEGIN QUOTE; rm_underscore(); strtext = new string( yytext, yyleng ); }
349<QUOTE>[^'\\\n]* { strtext->append( yytext, yyleng ); }
350<QUOTE>['\n] { BEGIN 0; strtext->append( yytext, yyleng ); RETURN_STR(CHARACTERconstant); }
351 /* ' stop editor highlighting */
352
353 /* string constant */
354({swide_prefix}[_]?)?["] { BEGIN STRING; rm_underscore(); strtext = new string( yytext, yyleng ); }
355<STRING>[^"\\\n]* { strtext->append( yytext, yyleng ); }
356<STRING>["\n] { BEGIN 0; strtext->append( yytext, yyleng ); RETURN_STR(STRINGliteral); }
357 /* " stop editor highlighting */
358
359 /* common character/string constant */
360<QUOTE,STRING>{escape_seq} { rm_underscore(); strtext->append( yytext, yyleng ); }
361<QUOTE,STRING>"\\"{h_white}*"\n" {} // continuation (ALSO HANDLED BY CPP)
362<QUOTE,STRING>"\\" { strtext->append( yytext, yyleng ); } // unknown escape character
363
364 /* punctuation */
365"@" { ASCIIOP_RETURN(); }
366"`" { ASCIIOP_RETURN(); }
367"[" { ASCIIOP_RETURN(); }
368"]" { ASCIIOP_RETURN(); }
369"(" { ASCIIOP_RETURN(); }
370")" { ASCIIOP_RETURN(); }
371"{" { ASCIIOP_RETURN(); }
372"}" { ASCIIOP_RETURN(); }
373"," { ASCIIOP_RETURN(); } // also operator
374":" { ASCIIOP_RETURN(); }
375";" { ASCIIOP_RETURN(); }
376"." { ASCIIOP_RETURN(); } // also operator
377"..." { NAMEDOP_RETURN(ELLIPSIS); }
378
379 /* alternative C99 brackets, "<:" & "<:<:" handled by preprocessor */
380"<:" { RETURN_VAL('['); }
381":>" { RETURN_VAL(']'); }
382"<%" { RETURN_VAL('{'); }
383"%>" { RETURN_VAL('}'); }
384
385 /* operators */
386"!" { ASCIIOP_RETURN(); }
387"+" { ASCIIOP_RETURN(); }
388"-" { ASCIIOP_RETURN(); }
389"*" { ASCIIOP_RETURN(); }
390"\\" { ASCIIOP_RETURN(); } // CFA, exponentiation
391"/" { ASCIIOP_RETURN(); }
392"%" { ASCIIOP_RETURN(); }
393"^" { ASCIIOP_RETURN(); }
394"~" { ASCIIOP_RETURN(); }
395"&" { ASCIIOP_RETURN(); }
396"|" { ASCIIOP_RETURN(); }
397"<" { ASCIIOP_RETURN(); }
398">" { ASCIIOP_RETURN(); }
399"=" { ASCIIOP_RETURN(); }
400"?" { ASCIIOP_RETURN(); }
401
402"++" { NAMEDOP_RETURN(ICR); }
403"--" { NAMEDOP_RETURN(DECR); }
404"==" { NAMEDOP_RETURN(EQ); }
405"!=" { NAMEDOP_RETURN(NE); }
406"<<" { NAMEDOP_RETURN(LS); }
407">>" { NAMEDOP_RETURN(RS); }
408"<=" { NAMEDOP_RETURN(LE); }
409">=" { NAMEDOP_RETURN(GE); }
410"&&" { NAMEDOP_RETURN(ANDAND); }
411"||" { NAMEDOP_RETURN(OROR); }
412"->" { NAMEDOP_RETURN(ARROW); }
413"+=" { NAMEDOP_RETURN(PLUSassign); }
414"-=" { NAMEDOP_RETURN(MINUSassign); }
415"\\=" { NAMEDOP_RETURN(EXPassign); } // CFA, exponentiation
416"*=" { NAMEDOP_RETURN(MULTassign); }
417"/=" { NAMEDOP_RETURN(DIVassign); }
418"%=" { NAMEDOP_RETURN(MODassign); }
419"&=" { NAMEDOP_RETURN(ANDassign); }
420"|=" { NAMEDOP_RETURN(ORassign); }
421"^=" { NAMEDOP_RETURN(ERassign); }
422"<<=" { NAMEDOP_RETURN(LSassign); }
423">>=" { NAMEDOP_RETURN(RSassign); }
424
425"@=" { NAMEDOP_RETURN(ATassign); } // CFA
426"~=" { NAMEDOP_RETURN(ErangeUpEq); } // CFA
427"-~" { NAMEDOP_RETURN(ErangeDown); } // CFA
428"-~=" { NAMEDOP_RETURN(ErangeDownEq); } // CFA
429
430 /* CFA, operator identifier */
431{op_unary}"?" { IDENTIFIER_RETURN(); } // unary
432"?"({op_unary_pre_post}|"()"|"[?]"|"{}") { IDENTIFIER_RETURN(); }
433"^?{}" { IDENTIFIER_RETURN(); }
434"?`"{identifier} { IDENTIFIER_RETURN(); } // postfix operator
435"?"{op_binary_over}"?" { IDENTIFIER_RETURN(); } // binary
436 /*
437 This rule handles ambiguous cases with operator identifiers, e.g., "int *?*?()", where the string "*?*?" can be
438 lexed as "*?"/"*?" or "*"/"?*?". Since it is common practise to put a unary operator juxtaposed to an identifier,
439 e.g., "*i", users will be annoyed if they cannot do this with respect to operator identifiers. Therefore, there is
440 a lexical look-ahead for the second case, with backtracking to return the leading unary operator and then
441 reparsing the trailing operator identifier. Otherwise a space is needed between the unary operator and operator
442 identifier to disambiguate this common case.
443
444 A similar issue occurs with the dereference, *?(...), and routine-call, ?()(...) identifiers. The ambiguity
445 occurs when the deference operator has no parameters, *?() and *?()(...), requiring arbitrary whitespace
446 look-ahead for the routine-call parameter-list to disambiguate. However, the dereference operator must have a
447 parameter/argument to dereference *?(...). Hence, always interpreting the string *?() as * ?() does not preclude
448 any meaningful program.
449
450 The remaining cases are with the increment/decrement operators and conditional expression:
451
452 i++? ...(...);
453 i?++ ...(...);
454
455 requiring arbitrary whitespace look-ahead for the operator parameter-list, even though that interpretation is an
456 incorrect expression (juxtaposed identifiers). Therefore, it is necessary to disambiguate these cases with a
457 space:
458
459 i++ ? i : 0;
460 i? ++i : 0;
461 */
462{op_unary}"?"({op_unary_pre_post}|"()"|"[?]"|{op_binary_over}"?") {
463 // 1 or 2 character unary operator ?
464 int i = yytext[1] == '?' ? 1 : 2;
465 yyless( i ); // put back characters up to first '?'
466 if ( i > 1 ) {
467 NAMEDOP_RETURN( yytext[0] == '+' ? ICR : DECR );
468 } else {
469 ASCIIOP_RETURN();
470 } // if
471}
472
473 /* unknown character */
474. { yyerror( "unknown character" ); }
475
476%%
477
478// ----end of lexer----
479
480void yyerror( const char * errmsg ) {
481 SemanticErrorThrow = true;
482 cerr << (yyfilename ? yyfilename : "*unknown file*") << ':' << yylineno << ':' << column - yyleng + 1
483 << ": " << ErrorHelpers::error_str() << errmsg << " at token \"" << (yytext[0] == '\0' ? "EOF" : yytext) << '"' << endl;
484}
485
486// Local Variables: //
487// mode: c++ //
488// tab-width: 4 //
489// compile-command: "make install" //
490// End: //
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