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lex.ll@ bc3127d

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ADT aaron-thesis arm-eh ast-experimental cleanup-dtors deferred_resn demangler enum forall-pointer-decay jacob/cs343-translation jenkins-sandbox new-ast new-ast-unique-expr new-env no_list persistent-indexer pthread-emulation qualifiedEnum resolv-new with_gc

Last change on this file since bc3127d was 76c62b2, checked in by Peter A. Buhr <pabuhr@…>, 8 years ago
first attempt at user-defined constants (units)
Property mode set to `100644`
File size: 17.6 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 : Thu Aug 31 21:30:10 2017
13	* Update Count : 598
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	unsigned int column = 0; // position of the end of the last token parsed
28	#define YY_USER_ACTION column += yyleng; // trigger before each matching rule's action
29
30	#include <string>
31	#include <cstdio> // FILENAME_MAX
32	using namespace std;
33
34	#include "ParseNode.h"
35	#include "TypedefTable.h"
36
37	char *yyfilename;
38	string *strtext; // accumulate parts of character and string constant value
39
40	#define RETURN_LOCN(x) yylval.tok.loc.file = yyfilename; yylval.tok.loc.line = yylineno; return( x )
41	#define RETURN_VAL(x) yylval.tok.str = new string( yytext ); RETURN_LOCN( x )
42	#define RETURN_CHAR(x) yylval.tok.str = nullptr; RETURN_LOCN( x )
43	#define RETURN_STR(x) yylval.tok.str = strtext; RETURN_LOCN( x )
44
45	#define WHITE_RETURN(x) // do nothing
46	#define NEWLINE_RETURN() column = 0; WHITE_RETURN( '\n' )
47	#define ASCIIOP_RETURN() RETURN_CHAR( (int)yytext[0] ) // single character operator
48	#define NAMEDOP_RETURN(x) RETURN_CHAR( x ) // multichar operator, with a name
49	#define NUMERIC_RETURN(x) rm_underscore(); RETURN_VAL( x ) // numeric constant
50	#define KEYWORD_RETURN(x) RETURN_CHAR( x ) // keyword
51	#define QKEYWORD_RETURN(x) typedefTable.isKind( yytext ); RETURN_VAL(x); // quasi-keyword
52	#define IDENTIFIER_RETURN() RETURN_VAL( typedefTable.isKind( yytext ) )
53	#define ATTRIBUTE_RETURN() RETURN_VAL( ATTR_IDENTIFIER )
54
55	void rm_underscore() {
56	// Remove underscores in numeric constant by copying the non-underscore characters to the front of the string.
57	yyleng = 0;
58	for ( int i = 0; yytext[i] != '\0'; i += 1 ) {
59	if ( yytext[i] == '`' ) {
60	// copy user suffix
61	for ( ; yytext[i] != '\0'; i += 1 ) {
62	yytext[yyleng] = yytext[i];
63	yyleng += 1;
64	} // for
65	break;
66	} // if
67	if ( yytext[i] != '_' ) {
68	yytext[yyleng] = yytext[i];
69	yyleng += 1;
70	} // if
71	} // for
72	yytext[yyleng] = '\0';
73	}
74
75	// Stop warning due to incorrectly generated flex code.
76	#pragma GCC diagnostic ignored "-Wsign-compare"
77	%}
78
79	octal [0-7]
80	nonzero [1-9]
81	decimal [0-9]
82	hex [0-9a-fA-F]
83	universal_char "\\"((u"_"?{hex_quad})\|(U"_"?{hex_quad}{2}))
84
85	// identifier, GCC: $ in identifier
86	identifier ([a-zA-Z_$]\|{universal_char})([0-9a-zA-Z_$]\|{universal_char})*
87
88	// attribute identifier, GCC: $ in identifier
89	attr_identifier "@"{identifier}
90
91	user_suffix_opt ("`"{identifier})?
92
93	// numeric constants, CFA: '_' in constant
94	hex_quad {hex}("_"?{hex}){3}
95	integer_suffix_opt ("_"?(([uU](("ll"\|"LL"\|[lL])[iI]\|[iI]?("ll"\|"LL"\|[lL])?))\|([iI](("ll"\|"LL"\|[lL])[uU]\|[uU]?("ll"\|"LL"\|[lL])?))\|(("ll"\|"LL"\|[lL])([iI][uU]\|[uU]?[iI]?))))?
96
97	octal_digits ({octal})\|({octal}({octal}\|"_")*{octal})
98	octal_prefix "0""_"?
99	octal_constant (("0")\|({octal_prefix}{octal_digits})){integer_suffix_opt}{user_suffix_opt}
100
101	nonzero_digits ({nonzero})\|({nonzero}({decimal}\|"_")*{decimal})
102	decimal_constant {nonzero_digits}{integer_suffix_opt}{user_suffix_opt}
103
104	hex_digits ({hex})\|({hex}({hex}\|"_")*{hex})
105	hex_prefix "0"[xX]"_"?
106	hex_constant {hex_prefix}{hex_digits}{integer_suffix_opt}{user_suffix_opt}
107
108	// GCC: D (double) and iI (imaginary) suffixes, and DL (long double)
109	floating_suffix_opt ("_"?([fFdDlL][iI]?\|[iI][lLfFdD]?\|"DL"))?
110	decimal_digits ({decimal})\|({decimal}({decimal}\|"_")*{decimal})
111	real_decimal {decimal_digits}"."{exponent}?{floating_suffix_opt}{user_suffix_opt}
112	real_fraction "."{decimal_digits}{exponent}?{floating_suffix_opt}{user_suffix_opt}
113	real_constant {decimal_digits}{real_fraction}
114	exponent "_"?[eE]"_"?[+-]?{decimal_digits}
115	floating_constant (({real_constant}{exponent}?)\|({decimal_digits}{exponent})){floating_suffix_opt}{user_suffix_opt}
116
117	binary_exponent "_"?[pP]"_"?[+-]?{decimal_digits}
118	hex_fractional_constant ({hex_digits}?"."{hex_digits})\|({hex_digits}".")
119	hex_floating_constant {hex_prefix}(({hex_fractional_constant}{binary_exponent})\|({hex_digits}{binary_exponent})){floating_suffix_opt}
120
121	// character escape sequence, GCC: \e => esc character
122	simple_escape "\\"[abefnrtv'"?\\]
123	// ' stop highlighting
124	octal_escape "\\"{octal}("_"?{octal}){0,2}
125	hex_escape "\\""x""_"?{hex_digits}
126	escape_seq {simple_escape}\|{octal_escape}\|{hex_escape}\|{universal_char}
127	cwide_prefix "L"\|"U"\|"u"
128	swide_prefix {cwide_prefix}\|"u8"
129
130	// display/white-space characters
131	h_tab [\011]
132	form_feed [\014]
133	v_tab [\013]
134	c_return [\015]
135	h_white [ ]\|{h_tab}
136
137	// overloadable operators
138	op_unary_only "~"\|"!"
139	op_unary_binary "+"\|"-"\|"*"
140	op_unary_pre_post "++"\|"--"
141	op_unary {op_unary_only}\|{op_unary_binary}\|{op_unary_pre_post}
142
143	op_binary_only "/"\|"%"\|"\\"\|"^"\|"&"\|"\|"\|"<"\|">"\|"="\|"=="\|"!="\|"<<"\|">>"\|"<="\|">="\|"+="\|"-="\|"*="\|"/="\|"%="\|"\\="\|"&="\|"\|="\|"^="\|"<<="\|">>="
144	op_binary_over {op_unary_binary}\|{op_binary_only}
145	// op_binary_not_over "?"\|"->"\|"."\|"&&"\|"\|\|"\|"@="
146	// operator {op_unary_pre_post}\|{op_binary_over}\|{op_binary_not_over}
147
148	%x COMMENT
149	%x BKQUOTE
150	%x QUOTE
151	%x STRING
152
153	%%
154	/* line directives */
155	^{h_white}"#"{h_white}[0-9]+{h_white}["][^"\n]+["]."\n" {
156	/* " stop highlighting */
157	static char filename[FILENAME_MAX]; // temporarily store current source-file name
158	char *end_num;
159	char begin_string, end_string;
160	long lineno, length;
161	lineno = strtol( yytext + 1, &end_num, 0 );
162	begin_string = strchr( end_num, '"' );
163	if ( begin_string ) { // file name ?
164	end_string = strchr( begin_string + 1, '"' ); // look for ending delimiter
165	assert( end_string ); // closing quote ?
166	length = end_string - begin_string - 1; // file-name length without quotes or sentinel
167	assert( length < FILENAME_MAX ); // room for sentinel ?
168	memcpy( &filename, begin_string + 1, length ); // copy file name from yytext
169	filename[ length ] = '\0'; // terminate string with sentinel
170	//cout << "file " << filename << " line " << lineno << endl;
171	yylineno = lineno;
172	yyfilename = filename;
173	} // if
174	}
175
176	/* ignore preprocessor directives (for now) */
177	^{h_white}"#"[^\n]"\n" ;
178
179	/* ignore C style comments (ALSO HANDLED BY CPP) */
180	"/*" { BEGIN COMMENT; }
181	<COMMENT>.\|\n ;
182	<COMMENT>"*/" { BEGIN 0; }
183
184	/* ignore C++ style comments (ALSO HANDLED BY CPP) */
185	"//"[^\n]*"\n" ;
186
187	/* ignore whitespace */
188	{h_white}+ { WHITE_RETURN(' '); }
189	({v_tab}\|{c_return}\|{form_feed})+ { WHITE_RETURN(' '); }
190	({h_white}\|{v_tab}\|{c_return}\|{form_feed})*"\n" { NEWLINE_RETURN(); }
191
192	/* keywords */
193	_Alignas { KEYWORD_RETURN(ALIGNAS); } // C11
194	_Alignof { KEYWORD_RETURN(ALIGNOF); } // C11
195	__alignof { KEYWORD_RETURN(ALIGNOF); } // GCC
196	__alignof__ { KEYWORD_RETURN(ALIGNOF); } // GCC
197	asm { KEYWORD_RETURN(ASM); }
198	__asm { KEYWORD_RETURN(ASM); } // GCC
199	__asm__ { KEYWORD_RETURN(ASM); } // GCC
200	_At { KEYWORD_RETURN(AT); } // CFA
201	_Atomic { KEYWORD_RETURN(ATOMIC); } // C11
202	__attribute { KEYWORD_RETURN(ATTRIBUTE); } // GCC
203	__attribute__ { KEYWORD_RETURN(ATTRIBUTE); } // GCC
204	auto { KEYWORD_RETURN(AUTO); }
205	_Bool { KEYWORD_RETURN(BOOL); } // C99
206	break { KEYWORD_RETURN(BREAK); }
207	case { KEYWORD_RETURN(CASE); }
208	catch { KEYWORD_RETURN(CATCH); } // CFA
209	catchResume { KEYWORD_RETURN(CATCHRESUME); } // CFA
210	char { KEYWORD_RETURN(CHAR); }
211	choose { KEYWORD_RETURN(CHOOSE); } // CFA
212	_Complex { KEYWORD_RETURN(COMPLEX); } // C99
213	__complex { KEYWORD_RETURN(COMPLEX); } // GCC
214	__complex__ { KEYWORD_RETURN(COMPLEX); } // GCC
215	const { KEYWORD_RETURN(CONST); }
216	__const { KEYWORD_RETURN(CONST); } // GCC
217	__const__ { KEYWORD_RETURN(CONST); } // GCC
218	continue { KEYWORD_RETURN(CONTINUE); }
219	coroutine { KEYWORD_RETURN(COROUTINE); } // CFA
220	default { KEYWORD_RETURN(DEFAULT); }
221	disable { KEYWORD_RETURN(DISABLE); } // CFA
222	do { KEYWORD_RETURN(DO); }
223	double { KEYWORD_RETURN(DOUBLE); }
224	dtype { KEYWORD_RETURN(DTYPE); } // CFA
225	else { KEYWORD_RETURN(ELSE); }
226	enable { KEYWORD_RETURN(ENABLE); } // CFA
227	enum { KEYWORD_RETURN(ENUM); }
228	__extension__ { KEYWORD_RETURN(EXTENSION); } // GCC
229	extern { KEYWORD_RETURN(EXTERN); }
230	fallthrough { KEYWORD_RETURN(FALLTHRU); } // CFA
231	fallthru { KEYWORD_RETURN(FALLTHRU); } // CFA
232	finally { KEYWORD_RETURN(FINALLY); } // CFA
233	float { KEYWORD_RETURN(FLOAT); }
234	__float128 { KEYWORD_RETURN(FLOAT); } // GCC
235	for { KEYWORD_RETURN(FOR); }
236	forall { KEYWORD_RETURN(FORALL); } // CFA
237	fortran { KEYWORD_RETURN(FORTRAN); }
238	ftype { KEYWORD_RETURN(FTYPE); } // CFA
239	_Generic { KEYWORD_RETURN(GENERIC); } // C11
240	goto { KEYWORD_RETURN(GOTO); }
241	if { KEYWORD_RETURN(IF); }
242	_Imaginary { KEYWORD_RETURN(IMAGINARY); } // C99
243	__imag { KEYWORD_RETURN(IMAGINARY); } // GCC
244	__imag__ { KEYWORD_RETURN(IMAGINARY); } // GCC
245	inline { KEYWORD_RETURN(INLINE); } // C99
246	__inline { KEYWORD_RETURN(INLINE); } // GCC
247	__inline__ { KEYWORD_RETURN(INLINE); } // GCC
248	int { KEYWORD_RETURN(INT); }
249	__int128 { KEYWORD_RETURN(INT); } // GCC
250	__int128_t { KEYWORD_RETURN(INT); } // GCC
251	__label__ { KEYWORD_RETURN(LABEL); } // GCC
252	long { KEYWORD_RETURN(LONG); }
253	monitor { KEYWORD_RETURN(MONITOR); } // CFA
254	mutex { KEYWORD_RETURN(MUTEX); } // CFA
255	_Noreturn { KEYWORD_RETURN(NORETURN); } // C11
256	__builtin_offsetof { KEYWORD_RETURN(OFFSETOF); } // GCC
257	one_t { NUMERIC_RETURN(ONE_T); } // CFA
258	otype { KEYWORD_RETURN(OTYPE); } // CFA
259	register { KEYWORD_RETURN(REGISTER); }
260	restrict { KEYWORD_RETURN(RESTRICT); } // C99
261	__restrict { KEYWORD_RETURN(RESTRICT); } // GCC
262	__restrict__ { KEYWORD_RETURN(RESTRICT); } // GCC
263	return { KEYWORD_RETURN(RETURN); }
264	short { KEYWORD_RETURN(SHORT); }
265	signed { KEYWORD_RETURN(SIGNED); }
266	__signed { KEYWORD_RETURN(SIGNED); } // GCC
267	__signed__ { KEYWORD_RETURN(SIGNED); } // GCC
268	sizeof { KEYWORD_RETURN(SIZEOF); }
269	static { KEYWORD_RETURN(STATIC); }
270	_Static_assert { KEYWORD_RETURN(STATICASSERT); } // C11
271	struct { KEYWORD_RETURN(STRUCT); }
272	switch { KEYWORD_RETURN(SWITCH); }
273	thread { KEYWORD_RETURN(THREAD); } // C11
274	_Thread_local { KEYWORD_RETURN(THREADLOCAL); } // C11
275	throw { KEYWORD_RETURN(THROW); } // CFA
276	throwResume { KEYWORD_RETURN(THROWRESUME); } // CFA
277	timeout { QKEYWORD_RETURN(TIMEOUT); } // CFA
278	trait { KEYWORD_RETURN(TRAIT); } // CFA
279	try { KEYWORD_RETURN(TRY); } // CFA
280	ttype { KEYWORD_RETURN(TTYPE); } // CFA
281	typedef { KEYWORD_RETURN(TYPEDEF); }
282	typeof { KEYWORD_RETURN(TYPEOF); } // GCC
283	__typeof { KEYWORD_RETURN(TYPEOF); } // GCC
284	__typeof__ { KEYWORD_RETURN(TYPEOF); } // GCC
285	__uint128_t { KEYWORD_RETURN(INT); } // GCC
286	union { KEYWORD_RETURN(UNION); }
287	unsigned { KEYWORD_RETURN(UNSIGNED); }
288	__builtin_va_list { KEYWORD_RETURN(VALIST); } // GCC
289	virtual { KEYWORD_RETURN(VIRTUAL); } // CFA
290	void { KEYWORD_RETURN(VOID); }
291	volatile { KEYWORD_RETURN(VOLATILE); }
292	__volatile { KEYWORD_RETURN(VOLATILE); } // GCC
293	__volatile__ { KEYWORD_RETURN(VOLATILE); } // GCC
294	waitfor { KEYWORD_RETURN(WAITFOR); }
295	or { QKEYWORD_RETURN(WOR); } // CFA
296	when { KEYWORD_RETURN(WHEN); }
297	while { KEYWORD_RETURN(WHILE); }
298	with { KEYWORD_RETURN(WITH); } // CFA
299	zero_t { NUMERIC_RETURN(ZERO_T); } // CFA
300
301	/* identifier */
302	{identifier} { IDENTIFIER_RETURN(); }
303	{attr_identifier} { ATTRIBUTE_RETURN(); }
304	"`" { BEGIN BKQUOTE; }
305	<BKQUOTE>{identifier} { IDENTIFIER_RETURN(); }
306	<BKQUOTE>"`" { BEGIN 0; }
307
308	/* numeric constants */
309	{decimal_constant} { NUMERIC_RETURN(INTEGERconstant); }
310	{octal_constant} { NUMERIC_RETURN(INTEGERconstant); }
311	{hex_constant} { NUMERIC_RETURN(INTEGERconstant); }
312	{real_decimal} { NUMERIC_RETURN(REALDECIMALconstant); } // must appear before floating_constant
313	{real_fraction} { NUMERIC_RETURN(REALFRACTIONconstant); } // must appear before floating_constant
314	{floating_constant} { NUMERIC_RETURN(FLOATINGconstant); }
315	{hex_floating_constant} { NUMERIC_RETURN(FLOATINGconstant); }
316
317	/* character constant, allows empty value */
318	({cwide_prefix}[_]?)?['] { BEGIN QUOTE; rm_underscore(); strtext = new string( yytext, yyleng ); }
319	<QUOTE>[^'\\\n]* { strtext->append( yytext, yyleng ); }
320	<QUOTE>['\n]{user_suffix_opt} { BEGIN 0; strtext->append( yytext, yyleng ); RETURN_STR(CHARACTERconstant); }
321	/* ' stop highlighting */
322
323	/* string constant */
324	({swide_prefix}[_]?)?["] { BEGIN STRING; rm_underscore(); strtext = new string( yytext, yyleng ); }
325	<STRING>[^"\\\n]* { strtext->append( yytext, yyleng ); }
326	<STRING>["\n]{user_suffix_opt} { BEGIN 0; strtext->append( yytext, yyleng ); RETURN_STR(STRINGliteral); }
327	/* " stop highlighting */
328
329	/* common character/string constant */
330	<QUOTE,STRING>{escape_seq} { rm_underscore(); strtext->append( yytext, yyleng ); }
331	<QUOTE,STRING>"\\"{h_white}*"\n" {} // continuation (ALSO HANDLED BY CPP)
332	<QUOTE,STRING>"\\" { strtext->append( yytext, yyleng ); } // unknown escape character
333
334	/* punctuation */
335	"@" { ASCIIOP_RETURN(); }
336	"[" { ASCIIOP_RETURN(); }
337	"]" { ASCIIOP_RETURN(); }
338	"(" { ASCIIOP_RETURN(); }
339	")" { ASCIIOP_RETURN(); }
340	"{" { ASCIIOP_RETURN(); }
341	"}" { ASCIIOP_RETURN(); }
342	"," { ASCIIOP_RETURN(); } // also operator
343	":" { ASCIIOP_RETURN(); }
344	";" { ASCIIOP_RETURN(); }
345	"." { ASCIIOP_RETURN(); } // also operator
346	"..." { NAMEDOP_RETURN(ELLIPSIS); }
347
348	/* alternative C99 brackets, "<:" & "<:<:" handled by preprocessor */
349	"<:" { RETURN_VAL('['); }
350	":>" { RETURN_VAL(']'); }
351	"<%" { RETURN_VAL('{'); }
352	"%>" { RETURN_VAL('}'); }
353
354	/* operators */
355	"!" { ASCIIOP_RETURN(); }
356	"+" { ASCIIOP_RETURN(); }
357	"-" { ASCIIOP_RETURN(); }
358	"*" { ASCIIOP_RETURN(); }
359	"\\" { ASCIIOP_RETURN(); } // CFA, exponentiation
360	"/" { ASCIIOP_RETURN(); }
361	"%" { ASCIIOP_RETURN(); }
362	"^" { ASCIIOP_RETURN(); }
363	"~" { ASCIIOP_RETURN(); }
364	"&" { ASCIIOP_RETURN(); }
365	"\|" { ASCIIOP_RETURN(); }
366	"<" { ASCIIOP_RETURN(); }
367	">" { ASCIIOP_RETURN(); }
368	"=" { ASCIIOP_RETURN(); }
369	"?" { ASCIIOP_RETURN(); }
370
371	"++" { NAMEDOP_RETURN(ICR); }
372	"--" { NAMEDOP_RETURN(DECR); }
373	"==" { NAMEDOP_RETURN(EQ); }
374	"!=" { NAMEDOP_RETURN(NE); }
375	"<<" { NAMEDOP_RETURN(LS); }
376	">>" { NAMEDOP_RETURN(RS); }
377	"<=" { NAMEDOP_RETURN(LE); }
378	">=" { NAMEDOP_RETURN(GE); }
379	"&&" { NAMEDOP_RETURN(ANDAND); }
380	"\|\|" { NAMEDOP_RETURN(OROR); }
381	"->" { NAMEDOP_RETURN(ARROW); }
382	"+=" { NAMEDOP_RETURN(PLUSassign); }
383	"-=" { NAMEDOP_RETURN(MINUSassign); }
384	"\\=" { NAMEDOP_RETURN(EXPassign); } // CFA, exponentiation
385	"*=" { NAMEDOP_RETURN(MULTassign); }
386	"/=" { NAMEDOP_RETURN(DIVassign); }
387	"%=" { NAMEDOP_RETURN(MODassign); }
388	"&=" { NAMEDOP_RETURN(ANDassign); }
389	"\|=" { NAMEDOP_RETURN(ORassign); }
390	"^=" { NAMEDOP_RETURN(ERassign); }
391	"<<=" { NAMEDOP_RETURN(LSassign); }
392	">>=" { NAMEDOP_RETURN(RSassign); }
393
394	"@=" { NAMEDOP_RETURN(ATassign); } // CFA
395
396	/* CFA, operator identifier */
397	{op_unary}"?" { IDENTIFIER_RETURN(); } // unary
398	"?"({op_unary_pre_post}\|"()"\|"[?]"\|"{}") { IDENTIFIER_RETURN(); }
399	"^?{}" { IDENTIFIER_RETURN(); }
400	"?`"{identifier} { IDENTIFIER_RETURN(); } // unit operator
401	"?"{op_binary_over}"?" { IDENTIFIER_RETURN(); } // binary
402	/*
403	This rule handles ambiguous cases with operator identifiers, e.g., "int ??()", where the string "??" can be
404	lexed as "?"/"?" or ""/"??". Since it is common practise to put a unary operator juxtaposed to an identifier,
405	e.g., "*i", users will be annoyed if they cannot do this with respect to operator identifiers. Therefore, there is
406	a lexical look-ahead for the second case, with backtracking to return the leading unary operator and then
407	reparsing the trailing operator identifier. Otherwise a space is needed between the unary operator and operator
408	identifier to disambiguate this common case.
409
410	A similar issue occurs with the dereference, *?(...), and routine-call, ?()(...) identifiers. The ambiguity
411	occurs when the deference operator has no parameters, ?() and ?()(...), requiring arbitrary whitespace
412	look-ahead for the routine-call parameter-list to disambiguate. However, the dereference operator must have a
413	parameter/argument to dereference ?(...). Hence, always interpreting the string ?() as * ?() does not preclude
414	any meaningful program.
415
416	The remaining cases are with the increment/decrement operators and conditional expression:
417
418	i++? ...(...);
419	i?++ ...(...);
420
421	requiring arbitrary whitespace look-ahead for the operator parameter-list, even though that interpretation is an
422	incorrect expression (juxtaposed identifiers). Therefore, it is necessary to disambiguate these cases with a
423	space:
424
425	i++ ? i : 0;
426	i? ++i : 0;
427	*/
428	{op_unary}"?"({op_unary_pre_post}\|"()"\|"[?]"\|{op_binary_over}"?") {
429	// 1 or 2 character unary operator ?
430	int i = yytext[1] == '?' ? 1 : 2;
431	yyless( i ); // put back characters up to first '?'
432	if ( i > 1 ) {
433	NAMEDOP_RETURN( yytext[0] == '+' ? ICR : DECR );
434	} else {
435	ASCIIOP_RETURN();
436	} // if
437	}
438
439	/* unknown character */
440	. { yyerror( "unknown character" ); }
441
442	%%
443	// ----end of lexer----
444
445	void yyerror( const char * errmsg ) {
446	cout << (yyfilename ? yyfilename : "unknown file") << ':' << yylineno << ':' << column - yyleng + 1
447	<< ": " << SemanticError::error_str() << errmsg << " at token \"" << (yytext[0] == '\0' ? "EOF" : yytext) << '"' << endl;
448	}
449
450	// Local Variables: //
451	// mode: c++ //
452	// tab-width: 4 //
453	// compile-command: "make install" //
454	// End: //

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