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lex.ll@ 3403534

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ADT aaron-thesis arm-eh ast-experimental cleanup-dtors ctor 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 3403534 was c1c1112, checked in by Peter A. Buhr <pabuhr@…>, 9 years ago
fix segment fault when printing syntax error, more refactoring of parser code
Property mode set to `100644`
File size: 15.7 KB

Rev	Line
[b87a5ed]	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.
[51b73452]	6	*
	7	* lex.l --
	8	*
	9	* Author : Peter A. Buhr
	10	* Created On : Sat Sep 22 08:58:10 2001
[926af74]	11	* Last Modified By : Peter A. Buhr
[c1c1112]	12	* Last Modified On : Wed Aug 24 13:27:04 2016
	13	* Update Count : 487
[51b73452]	14	*/
	15
	16	%option yylineno
[5f2f2d7]	17	%option nounput
[51b73452]	18
	19	%{
[de62360d]	20	// This lexer assumes the program has been preprocessed by cpp. Hence, all user level preprocessor directive have been
	21	// performed and removed from the source. The only exceptions are preprocessor directives passed to the compiler (e.g.,
	22	// line-number directives) and C/C++ style comments, which are ignored.
[51b73452]	23
[8c17ab0]	24	//************************** Includes and Defines **************************
[51b73452]	25
	26	#include <string>
[f487962]	27	#include <cstdio> // FILENAME_MAX
[51b73452]	28
	29	#include "lex.h"
[59db689]	30	#include "parser.h" // YACC generated definitions based on C++ grammar
[984dce6]	31	#include "ParseNode.h"
	32	#include "TypedefTable.h"
[51b73452]	33
	34	char *yyfilename;
[b87a5ed]	35	std::string *strtext; // accumulate parts of character and string constant value
[51b73452]	36
[de62360d]	37	#define RETURN_LOCN(x) yylval.tok.loc.file = yyfilename; yylval.tok.loc.line = yylineno; return( x )
	38	#define RETURN_VAL(x) yylval.tok.str = new std::string( yytext ); RETURN_LOCN( x )
[926af74]	39	#define RETURN_CHAR(x) yylval.tok.str = nullptr; RETURN_LOCN( x )
[de62360d]	40	#define RETURN_STR(x) yylval.tok.str = strtext; RETURN_LOCN( x )
[5f2f2d7]	41
[f487962]	42	#define WHITE_RETURN(x) // do nothing
[de62360d]	43	#define NEWLINE_RETURN() WHITE_RETURN( '\n' )
	44	#define ASCIIOP_RETURN() RETURN_CHAR( (int)yytext[0] ) // single character operator
[f487962]	45	#define NAMEDOP_RETURN(x) RETURN_CHAR( x ) // multichar operator, with a name
[de62360d]	46	#define NUMERIC_RETURN(x) rm_underscore(); RETURN_VAL( x ) // numeric constant
	47	#define KEYWORD_RETURN(x) RETURN_CHAR( x ) // keyword
[984dce6]	48	#define IDENTIFIER_RETURN() RETURN_VAL( typedefTable.isKind( yytext ) )
[de62360d]	49	#define ATTRIBUTE_RETURN() RETURN_VAL( ATTR_IDENTIFIER )
[51b73452]	50
[3848e0e]	51	void rm_underscore() {
[e7aed49]	52	// Remove underscores in numeric constant by copying the non-underscore characters to the front of the string.
	53	yyleng = 0;
[b87a5ed]	54	for ( int i = 0; yytext[i] != '\0'; i += 1 ) {
	55	if ( yytext[i] != '_' ) {
[e7aed49]	56	yytext[yyleng] = yytext[i];
	57	yyleng += 1;
[b87a5ed]	58	} // if
	59	} // for
	60	yytext[yyleng] = '\0';
[51b73452]	61	}
	62
	63	%}
	64
	65	octal [0-7]
	66	nonzero [1-9]
	67	decimal [0-9]
	68	hex [0-9a-fA-F]
[3848e0e]	69	universal_char "\\"((u"_"?{hex_quad})\|(U"_"?{hex_quad}{2}))
[51b73452]	70
[b87a5ed]	71	// identifier, GCC: $ in identifier
[51b73452]	72	identifier ([a-zA-Z_$]\|{universal_char})([0-9a-zA-Z_$]\|{universal_char})*
	73
[b87a5ed]	74	// quoted identifier
[8c17ab0]	75	quoted_identifier "`"{identifier}"`"
	76
[b87a5ed]	77	// attribute identifier, GCC: $ in identifier
[51b73452]	78	attr_identifier "@"{identifier}
	79
[b87a5ed]	80	// numeric constants, CFA: '_' in constant
[3848e0e]	81	hex_quad {hex}("_"?{hex}){3}
[51b73452]	82	integer_suffix "_"?(([uU][lL]?)\|([uU]("ll"\|"LL")?)\|([lL][uU]?)\|("ll"\|"LL")[uU]?)
	83
	84	octal_digits ({octal})\|({octal}({octal}\|"_")*{octal})
	85	octal_prefix "0""_"?
	86	octal_constant (("0")\|({octal_prefix}{octal_digits})){integer_suffix}?
	87
	88	nonzero_digits ({nonzero})\|({nonzero}({decimal}\|"_")*{decimal})
	89	decimal_constant {nonzero_digits}{integer_suffix}?
	90
	91	hex_digits ({hex})\|({hex}({hex}\|"_")*{hex})
	92	hex_prefix "0"[xX]"_"?
	93	hex_constant {hex_prefix}{hex_digits}{integer_suffix}?
	94
	95	decimal_digits ({decimal})\|({decimal}({decimal}\|"_")*{decimal})
	96	fractional_constant ({decimal_digits}?"."{decimal_digits})\|({decimal_digits}".")
	97	exponent "_"?[eE]"_"?[+-]?{decimal_digits}
[984dce6]	98	// GCC: D (double), DL (long double) and iI (imaginary) suffixes
	99	floating_suffix "_"?([fFdDlL][iI]?\|"DL"\|[iI][lLfFdD]?)
	100	//floating_suffix "_"?([fFdD]\|[lL]\|[D][L])\|([iI][lLfFdD])\|([lLfFdD][iI]))
[51b73452]	101	floating_constant (({fractional_constant}{exponent}?)\|({decimal_digits}{exponent})){floating_suffix}?
	102
	103	binary_exponent "_"?[pP]"_"?[+-]?{decimal_digits}
	104	hex_fractional_constant ({hex_digits}?"."{hex_digits})\|({hex_digits}".")
	105	hex_floating_constant {hex_prefix}(({hex_fractional_constant}{binary_exponent})\|({hex_digits}{binary_exponent})){floating_suffix}?
	106
[b87a5ed]	107	// character escape sequence, GCC: \e => esc character
[51b73452]	108	simple_escape "\\"[abefnrtv'"?\\]
[b87a5ed]	109	// ' stop highlighting
[3848e0e]	110	octal_escape "\\"{octal}("_"?{octal}){0,2}
	111	hex_escape "\\""x""_"?{hex_digits}
[51b73452]	112	escape_seq {simple_escape}\|{octal_escape}\|{hex_escape}\|{universal_char}
[59db689]	113	cwide_prefix "L"\|"U"\|"u"
	114	swide_prefix {cwide_prefix}\|"u8"
[51b73452]	115
[b87a5ed]	116	// display/white-space characters
[51b73452]	117	h_tab [\011]
	118	form_feed [\014]
	119	v_tab [\013]
	120	c_return [\015]
	121	h_white [ ]\|{h_tab}
	122
[e7aed49]	123	// overloadable operators
[51b73452]	124	op_unary_only "~"\|"!"
	125	op_unary_binary "+"\|"-"\|"*"
	126	op_unary_pre_post "++"\|"--"
	127	op_unary {op_unary_only}\|{op_unary_binary}\|{op_unary_pre_post}
	128
	129	op_binary_only "/"\|"%"\|"^"\|"&"\|"\|"\|"<"\|">"\|"="\|"=="\|"!="\|"<<"\|">>"\|"<="\|">="\|"+="\|"-="\|"*="\|"/="\|"%="\|"&="\|"\|="\|"^="\|"<<="\|">>="
	130	op_binary_over {op_unary_binary}\|{op_binary_only}
[e7aed49]	131	// op_binary_not_over "?"\|"->"\|"."\|"&&"\|"\|\|"\|"@="
	132	// operator {op_unary_pre_post}\|{op_binary_over}\|{op_binary_not_over}
[51b73452]	133
	134	%x COMMENT
[3848e0e]	135	%x BKQUOTE
	136	%x QUOTE
	137	%x STRING
[51b73452]	138
	139	%%
[b87a5ed]	140	/* line directives */
[4040425]	141	^{h_white}"#"{h_white}[0-9]+{h_white}["][^"\n]+["]."\n" {
[8c17ab0]	142	/* " stop highlighting */
[c1c1112]	143	static char filename[FILENAME_MAX]; // temporarily store current source-file name
[51b73452]	144	char *end_num;
	145	char begin_string, end_string;
	146	long lineno, length;
	147	lineno = strtol( yytext + 1, &end_num, 0 );
	148	begin_string = strchr( end_num, '"' );
[f487962]	149	if ( begin_string ) { // file name ?
	150	end_string = strchr( begin_string + 1, '"' ); // look for ending delimiter
	151	assert( end_string ); // closing quote ?
	152	length = end_string - begin_string - 1; // file-name length without quotes or sentinel
	153	assert( length < FILENAME_MAX ); // room for sentinel ?
	154	memcpy( &filename, begin_string + 1, length ); // copy file name from yytext
	155	filename[ length ] = '\0'; // terminate string with sentinel
	156	//std::cout << "file " << filename << " line " << lineno << std::endl;
	157	yylineno = lineno;
[c1c1112]	158	yyfilename = filename;
[b87a5ed]	159	} // if
[51b73452]	160	}
	161
[b87a5ed]	162	/* ignore preprocessor directives (for now) */
[51b73452]	163	^{h_white}"#"[^\n]"\n" ;
	164
[cd623a4]	165	/* ignore C style comments (ALSO HANDLED BY CPP) */
[3848e0e]	166	"/*" { BEGIN COMMENT; }
[cd623a4]	167	<COMMENT>.\|\n ;
	168	<COMMENT>"*/" { BEGIN 0; }
[51b73452]	169
[cd623a4]	170	/* ignore C++ style comments (ALSO HANDLED BY CPP) */
	171	"//"[^\n]*"\n" ;
[51b73452]	172
[b87a5ed]	173	/* ignore whitespace */
[3848e0e]	174	{h_white}+ { WHITE_RETURN(' '); }
	175	({v_tab}\|{c_return}\|{form_feed})+ { WHITE_RETURN(' '); }
	176	({h_white}\|{v_tab}\|{c_return}\|{form_feed})*"\n" { NEWLINE_RETURN(); }
[51b73452]	177
[b87a5ed]	178	/* keywords */
	179	_Alignas { KEYWORD_RETURN(ALIGNAS); } // C11
	180	_Alignof { KEYWORD_RETURN(ALIGNOF); } // C11
	181	__alignof { KEYWORD_RETURN(ALIGNOF); } // GCC
	182	__alignof__ { KEYWORD_RETURN(ALIGNOF); } // GCC
	183	asm { KEYWORD_RETURN(ASM); }
	184	__asm { KEYWORD_RETURN(ASM); } // GCC
	185	__asm__ { KEYWORD_RETURN(ASM); } // GCC
[02e5ab6]	186	_At { KEYWORD_RETURN(AT); } // CFA
[b87a5ed]	187	_Atomic { KEYWORD_RETURN(ATOMIC); } // C11
	188	__attribute { KEYWORD_RETURN(ATTRIBUTE); } // GCC
	189	__attribute__ { KEYWORD_RETURN(ATTRIBUTE); } // GCC
[3848e0e]	190	auto { KEYWORD_RETURN(AUTO); }
[b87a5ed]	191	_Bool { KEYWORD_RETURN(BOOL); } // C99
[3848e0e]	192	break { KEYWORD_RETURN(BREAK); }
	193	case { KEYWORD_RETURN(CASE); }
[b87a5ed]	194	catch { KEYWORD_RETURN(CATCH); } // CFA
[02e5ab6]	195	catchResume { KEYWORD_RETURN(CATCHRESUME); } // CFA
[3848e0e]	196	char { KEYWORD_RETURN(CHAR); }
[b87a5ed]	197	choose { KEYWORD_RETURN(CHOOSE); } // CFA
	198	_Complex { KEYWORD_RETURN(COMPLEX); } // C99
	199	__complex { KEYWORD_RETURN(COMPLEX); } // GCC
	200	__complex__ { KEYWORD_RETURN(COMPLEX); } // GCC
[3848e0e]	201	const { KEYWORD_RETURN(CONST); }
[b87a5ed]	202	__const { KEYWORD_RETURN(CONST); } // GCC
	203	__const__ { KEYWORD_RETURN(CONST); } // GCC
[3848e0e]	204	continue { KEYWORD_RETURN(CONTINUE); }
	205	default { KEYWORD_RETURN(DEFAULT); }
[02e5ab6]	206	disable { KEYWORD_RETURN(DISABLE); } // CFA
[b87a5ed]	207	do { KEYWORD_RETURN(DO); }
[3848e0e]	208	double { KEYWORD_RETURN(DOUBLE); }
[b87a5ed]	209	dtype { KEYWORD_RETURN(DTYPE); } // CFA
[3848e0e]	210	else { KEYWORD_RETURN(ELSE); }
[02e5ab6]	211	enable { KEYWORD_RETURN(ENABLE); } // CFA
[3848e0e]	212	enum { KEYWORD_RETURN(ENUM); }
[b87a5ed]	213	__extension__ { KEYWORD_RETURN(EXTENSION); } // GCC
[3848e0e]	214	extern { KEYWORD_RETURN(EXTERN); }
[08061589]	215	fallthrough { KEYWORD_RETURN(FALLTHRU); } // CFA
[b87a5ed]	216	fallthru { KEYWORD_RETURN(FALLTHRU); } // CFA
	217	finally { KEYWORD_RETURN(FINALLY); } // CFA
[3848e0e]	218	float { KEYWORD_RETURN(FLOAT); }
[b87a5ed]	219	__float128 { KEYWORD_RETURN(FLOAT); } // GCC
	220	for { KEYWORD_RETURN(FOR); }
	221	forall { KEYWORD_RETURN(FORALL); } // CFA
[3848e0e]	222	fortran { KEYWORD_RETURN(FORTRAN); }
[b87a5ed]	223	ftype { KEYWORD_RETURN(FTYPE); } // CFA
	224	_Generic { KEYWORD_RETURN(GENERIC); } // C11
[3848e0e]	225	goto { KEYWORD_RETURN(GOTO); }
[b87a5ed]	226	if { KEYWORD_RETURN(IF); }
	227	_Imaginary { KEYWORD_RETURN(IMAGINARY); } // C99
	228	__imag { KEYWORD_RETURN(IMAGINARY); } // GCC
	229	__imag__ { KEYWORD_RETURN(IMAGINARY); } // GCC
	230	inline { KEYWORD_RETURN(INLINE); } // C99
	231	__inline { KEYWORD_RETURN(INLINE); } // GCC
	232	__inline__ { KEYWORD_RETURN(INLINE); } // GCC
	233	int { KEYWORD_RETURN(INT); }
	234	__int128 { KEYWORD_RETURN(INT); } // GCC
	235	__label__ { KEYWORD_RETURN(LABEL); } // GCC
[3848e0e]	236	long { KEYWORD_RETURN(LONG); }
[b87a5ed]	237	lvalue { KEYWORD_RETURN(LVALUE); } // CFA
	238	_Noreturn { KEYWORD_RETURN(NORETURN); } // C11
[5721a6d]	239	__builtin_offsetof { KEYWORD_RETURN(OFFSETOF); } // GCC
[4040425]	240	otype { KEYWORD_RETURN(OTYPE); } // CFA
[3848e0e]	241	register { KEYWORD_RETURN(REGISTER); }
[b87a5ed]	242	restrict { KEYWORD_RETURN(RESTRICT); } // C99
	243	__restrict { KEYWORD_RETURN(RESTRICT); } // GCC
	244	__restrict__ { KEYWORD_RETURN(RESTRICT); } // GCC
[3848e0e]	245	return { KEYWORD_RETURN(RETURN); }
	246	short { KEYWORD_RETURN(SHORT); }
	247	signed { KEYWORD_RETURN(SIGNED); }
[b87a5ed]	248	__signed { KEYWORD_RETURN(SIGNED); } // GCC
	249	__signed__ { KEYWORD_RETURN(SIGNED); } // GCC
[3848e0e]	250	sizeof { KEYWORD_RETURN(SIZEOF); }
	251	static { KEYWORD_RETURN(STATIC); }
[b87a5ed]	252	_Static_assert { KEYWORD_RETURN(STATICASSERT); } // C11
[3848e0e]	253	struct { KEYWORD_RETURN(STRUCT); }
	254	switch { KEYWORD_RETURN(SWITCH); }
[b87a5ed]	255	_Thread_local { KEYWORD_RETURN(THREADLOCAL); } // C11
	256	throw { KEYWORD_RETURN(THROW); } // CFA
[02e5ab6]	257	throwResume { KEYWORD_RETURN(THROWRESUME); } // CFA
[4040425]	258	trait { KEYWORD_RETURN(TRAIT); } // CFA
[b87a5ed]	259	try { KEYWORD_RETURN(TRY); } // CFA
[3848e0e]	260	typedef { KEYWORD_RETURN(TYPEDEF); }
[b87a5ed]	261	typeof { KEYWORD_RETURN(TYPEOF); } // GCC
	262	__typeof { KEYWORD_RETURN(TYPEOF); } // GCC
	263	__typeof__ { KEYWORD_RETURN(TYPEOF); } // GCC
[3848e0e]	264	union { KEYWORD_RETURN(UNION); }
	265	unsigned { KEYWORD_RETURN(UNSIGNED); }
[90c3b1c]	266	__builtin_va_list { KEYWORD_RETURN(VALIST); } // GCC
[3848e0e]	267	void { KEYWORD_RETURN(VOID); }
	268	volatile { KEYWORD_RETURN(VOLATILE); }
[b87a5ed]	269	__volatile { KEYWORD_RETURN(VOLATILE); } // GCC
	270	__volatile__ { KEYWORD_RETURN(VOLATILE); } // GCC
[3848e0e]	271	while { KEYWORD_RETURN(WHILE); }
[51b73452]	272
[b87a5ed]	273	/* identifier */
	274	{identifier} { IDENTIFIER_RETURN(); }
	275	{attr_identifier} { ATTRIBUTE_RETURN(); }
[c6b1105]	276	"`" { BEGIN BKQUOTE; }
[b87a5ed]	277	<BKQUOTE>{identifier} { IDENTIFIER_RETURN(); }
	278	<BKQUOTE>"`" { BEGIN 0; }
[51b73452]	279
[b87a5ed]	280	/* numeric constants */
	281	"0" { NUMERIC_RETURN(ZERO); } // CFA
	282	"1" { NUMERIC_RETURN(ONE); } // CFA
[59db689]	283	{decimal_constant} { NUMERIC_RETURN(INTEGERconstant); }
	284	{octal_constant} { NUMERIC_RETURN(INTEGERconstant); }
	285	{hex_constant} { NUMERIC_RETURN(INTEGERconstant); }
[3848e0e]	286	{floating_constant} { NUMERIC_RETURN(FLOATINGconstant); }
	287	{hex_floating_constant} { NUMERIC_RETURN(FLOATINGconstant); }
[51b73452]	288
[b87a5ed]	289	/* character constant, allows empty value */
[c1c1112]	290	({cwide_prefix}[_]?)?['] { BEGIN QUOTE; rm_underscore(); strtext = new std::string( yytext, yyleng ); }
	291	<QUOTE>[^'\\\n]* { strtext->append( yytext, yyleng ); }
	292	<QUOTE>['\n] { BEGIN 0; strtext->append( yytext, yyleng ); RETURN_STR(CHARACTERconstant); }
[b87a5ed]	293	/* ' stop highlighting */
[51b73452]	294
[b87a5ed]	295	/* string constant */
[c1c1112]	296	({swide_prefix}[_]?)?["] { BEGIN STRING; rm_underscore(); strtext = new std::string( yytext, yyleng ); }
	297	<STRING>[^"\\\n]* { strtext->append( yytext, yyleng ); }
	298	<STRING>["\n] { BEGIN 0; strtext->append( yytext, yyleng ); RETURN_STR(STRINGliteral); }
[b87a5ed]	299	/* " stop highlighting */
[51b73452]	300
[59db689]	301	/* common character/string constant */
[c1c1112]	302	<QUOTE,STRING>{escape_seq} { rm_underscore(); strtext->append( yytext, yyleng ); }
[cd623a4]	303	<QUOTE,STRING>"\\"{h_white}*"\n" {} // continuation (ALSO HANDLED BY CPP)
[c1c1112]	304	<QUOTE,STRING>"\\" { strtext->append( yytext, yyleng ); } // unknown escape character
[3848e0e]	305
[b87a5ed]	306	/* punctuation */
	307	"[" { ASCIIOP_RETURN(); }
	308	"]" { ASCIIOP_RETURN(); }
	309	"(" { ASCIIOP_RETURN(); }
	310	")" { ASCIIOP_RETURN(); }
	311	"{" { ASCIIOP_RETURN(); }
	312	"}" { ASCIIOP_RETURN(); }
	313	"," { ASCIIOP_RETURN(); } // also operator
	314	":" { ASCIIOP_RETURN(); }
	315	";" { ASCIIOP_RETURN(); }
	316	"." { ASCIIOP_RETURN(); } // also operator
[3848e0e]	317	"..." { NAMEDOP_RETURN(ELLIPSIS); }
	318
[b87a5ed]	319	/* alternative C99 brackets, "<:" & "<:<:" handled by preprocessor */
[3848e0e]	320	"<:" { RETURN_VAL('['); }
	321	":>" { RETURN_VAL(']'); }
	322	"<%" { RETURN_VAL('{'); }
	323	"%>" { RETURN_VAL('}'); }
[51b73452]	324
[b87a5ed]	325	/* operators */
	326	"!" { ASCIIOP_RETURN(); }
	327	"+" { ASCIIOP_RETURN(); }
	328	"-" { ASCIIOP_RETURN(); }
	329	"*" { ASCIIOP_RETURN(); }
	330	"/" { ASCIIOP_RETURN(); }
	331	"%" { ASCIIOP_RETURN(); }
	332	"^" { ASCIIOP_RETURN(); }
	333	"~" { ASCIIOP_RETURN(); }
	334	"&" { ASCIIOP_RETURN(); }
	335	"\|" { ASCIIOP_RETURN(); }
	336	"<" { ASCIIOP_RETURN(); }
	337	">" { ASCIIOP_RETURN(); }
	338	"=" { ASCIIOP_RETURN(); }
	339	"?" { ASCIIOP_RETURN(); }
[3848e0e]	340
	341	"++" { NAMEDOP_RETURN(ICR); }
	342	"--" { NAMEDOP_RETURN(DECR); }
	343	"==" { NAMEDOP_RETURN(EQ); }
	344	"!=" { NAMEDOP_RETURN(NE); }
	345	"<<" { NAMEDOP_RETURN(LS); }
	346	">>" { NAMEDOP_RETURN(RS); }
	347	"<=" { NAMEDOP_RETURN(LE); }
	348	">=" { NAMEDOP_RETURN(GE); }
	349	"&&" { NAMEDOP_RETURN(ANDAND); }
	350	"\|\|" { NAMEDOP_RETURN(OROR); }
	351	"->" { NAMEDOP_RETURN(ARROW); }
	352	"+=" { NAMEDOP_RETURN(PLUSassign); }
	353	"-=" { NAMEDOP_RETURN(MINUSassign); }
	354	"*=" { NAMEDOP_RETURN(MULTassign); }
	355	"/=" { NAMEDOP_RETURN(DIVassign); }
	356	"%=" { NAMEDOP_RETURN(MODassign); }
	357	"&=" { NAMEDOP_RETURN(ANDassign); }
	358	"\|=" { NAMEDOP_RETURN(ORassign); }
	359	"^=" { NAMEDOP_RETURN(ERassign); }
	360	"<<=" { NAMEDOP_RETURN(LSassign); }
	361	">>=" { NAMEDOP_RETURN(RSassign); }
[51b73452]	362
[08061589]	363	"@=" { NAMEDOP_RETURN(ATassign); } // CFA
[097e2b0]	364
[b87a5ed]	365	/* CFA, operator identifier */
	366	{op_unary}"?" { IDENTIFIER_RETURN(); } // unary
[a61fea9a]	367	"?"({op_unary_pre_post}\|"()"\|"[?]"\|"{}") { IDENTIFIER_RETURN(); }
[02e5ab6]	368	"^?{}" { IDENTIFIER_RETURN(); }
[b87a5ed]	369	"?"{op_binary_over}"?" { IDENTIFIER_RETURN(); } // binary
[51b73452]	370	/*
[b87a5ed]	371	This rule handles ambiguous cases with operator identifiers, e.g., "int ??()", where the string "??"
	372	can be lexed as ""/"??" or "?"/"?". Since it is common practise to put a unary operator juxtaposed
	373	to an identifier, e.g., "*i", users will be annoyed if they cannot do this with respect to operator
	374	identifiers. Even with this special hack, there are 5 general cases that cannot be handled. The first
	375	case is for the function-call identifier "?()":
[51b73452]	376
	377	int * ?()(); // declaration: space required after '*'
	378	* ?()(); // expression: space required after '*'
	379
[b87a5ed]	380	Without the space, the string "*?()" is ambiguous without N character look ahead; it requires scanning
	381	ahead to determine if there is a '(', which is the start of an argument/parameter list.
[51b73452]	382
	383	The 4 remaining cases occur in expressions:
	384
	385	i++?i:0; // space required before '?'
	386	i--?i:0; // space required before '?'
	387	i?++i:0; // space required after '?'
	388	i?--i:0; // space required after '?'
	389
[b87a5ed]	390	In the first two cases, the string "i++?" is ambiguous, where this string can be lexed as "i"/"++?" or
	391	"i++"/"?"; it requires scanning ahead to determine if there is a '(', which is the start of an argument
	392	list. In the second two cases, the string "?++x" is ambiguous, where this string can be lexed as
	393	"?++"/"x" or "?"/"++x"; it requires scanning ahead to determine if there is a '(', which is the start of
	394	an argument list.
[51b73452]	395	*/
[02e5ab6]	396	{op_unary}"?"({op_unary_pre_post}\|"[?]"\|{op_binary_over}"?") {
[b87a5ed]	397	// 1 or 2 character unary operator ?
	398	int i = yytext[1] == '?' ? 1 : 2;
	399	yyless( i ); // put back characters up to first '?'
	400	if ( i > 1 ) {
	401	NAMEDOP_RETURN( yytext[0] == '+' ? ICR : DECR );
	402	} else {
	403	ASCIIOP_RETURN();
	404	} // if
	405	}
	406
	407	/* unknown characters */
[3848e0e]	408	. { printf("unknown character(s):\"%s\" on line %d\n", yytext, yylineno); }
[51b73452]	409
	410	%%
	411
[b87a5ed]	412	// Local Variables: //
	413	// mode: c++ //
[de62360d]	414	// tab-width: 4 //
[b87a5ed]	415	// compile-command: "make install" //
	416	// End: //

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