[51b7345] | 1 | /* -*- Mode: C -*- |
---|
| 2 | * |
---|
| 3 | * CForall Lexer Version 1.0, Copyright (C) Peter A. Buhr 2001 -- Permission is granted to copy this |
---|
| 4 | * grammar and to use it within software systems. THIS GRAMMAR IS PROVIDED "AS IS" AND WITHOUT |
---|
| 5 | * ANY EXPRESS OR IMPLIED WARRANTIES. |
---|
| 6 | * |
---|
| 7 | * lex.l -- |
---|
| 8 | * |
---|
| 9 | * Author : Peter A. Buhr |
---|
| 10 | * Created On : Sat Sep 22 08:58:10 2001 |
---|
| 11 | * Last Modified By : Peter A. Buhr |
---|
[8c17ab0] | 12 | * Last Modified On : Tue Nov 11 08:10:05 2014 |
---|
| 13 | * Update Count : 215 |
---|
[51b7345] | 14 | */ |
---|
| 15 | |
---|
| 16 | %option yylineno |
---|
| 17 | |
---|
| 18 | %{ |
---|
[8c17ab0] | 19 | // This lexer assumes the program has been preprocessed by cpp. Hence, all user level preprocessor |
---|
| 20 | // directive have been performed and removed from the source. The only exceptions are preprocessor |
---|
| 21 | // directives passed to the compiler (e.g., line-number directives) and C/C++ style comments, which |
---|
| 22 | // are ignored. |
---|
[51b7345] | 23 | |
---|
[8c17ab0] | 24 | //**************************** Includes and Defines **************************** |
---|
[51b7345] | 25 | |
---|
| 26 | #include <string> |
---|
| 27 | |
---|
| 28 | #include "lex.h" |
---|
| 29 | #include "ParseNode.h" |
---|
[8c17ab0] | 30 | #include "cfa.tab.h" // YACC generated definitions based on C++ grammar |
---|
[51b7345] | 31 | |
---|
| 32 | char *yyfilename; |
---|
| 33 | |
---|
[8c17ab0] | 34 | #define WHITE_RETURN(x) // do nothing |
---|
[51b7345] | 35 | #define NEWLINE_RETURN() WHITE_RETURN('\n') |
---|
| 36 | #define RETURN_VAL(x) yylval.tok.str = new std::string(yytext); \ |
---|
| 37 | yylval.tok.loc.file = yyfilename; \ |
---|
| 38 | yylval.tok.loc.line = yylineno; \ |
---|
| 39 | return(x) |
---|
| 40 | |
---|
[8c17ab0] | 41 | #define KEYWORD_RETURN(x) RETURN_VAL(x) // keyword |
---|
[51b7345] | 42 | #define IDENTIFIER_RETURN() RETURN_VAL((typedefTable.isIdentifier(yytext) ? IDENTIFIER : typedefTable.isTypedef(yytext) ? TYPEDEFname : TYPEGENname)) |
---|
[8c17ab0] | 43 | //#define ATTRIBUTE_RETURN() RETURN_VAL((typedefTable.isIdentifier(yytext) ? ATTR_IDENTIFIER : typedefTable.isTypedef(yytext) ? ATTR_TYPEDEFname : ATTR_TYPEGENname)) |
---|
| 44 | #define ATTRIBUTE_RETURN() RETURN_VAL(ATTR_IDENTIFIER) |
---|
[51b7345] | 45 | |
---|
[8c17ab0] | 46 | #define ASCIIOP_RETURN() RETURN_VAL((int)yytext[0]) // single character operator |
---|
| 47 | #define NAMEDOP_RETURN(x) RETURN_VAL(x) // multichar operator, with a name |
---|
[51b7345] | 48 | |
---|
[8c17ab0] | 49 | #define NUMERIC_RETURN(x) rm_underscore(); RETURN_VAL(x) // numeric constant |
---|
[51b7345] | 50 | |
---|
[8c17ab0] | 51 | void rm_underscore() { // remove underscores in constant or escape sequence |
---|
[51b7345] | 52 | int j = 0; |
---|
| 53 | for ( int i = 0; i < yyleng; i += 1 ) { |
---|
| 54 | if ( yytext[i] != '_' ) { |
---|
| 55 | yytext[j] = yytext[i]; |
---|
| 56 | j += 1; |
---|
| 57 | } // if |
---|
| 58 | } // for |
---|
| 59 | yyleng = j; |
---|
| 60 | yytext[yyleng] = '\0'; |
---|
| 61 | } |
---|
| 62 | |
---|
| 63 | %} |
---|
| 64 | |
---|
| 65 | octal [0-7] |
---|
| 66 | nonzero [1-9] |
---|
| 67 | decimal [0-9] |
---|
| 68 | hex [0-9a-fA-F] |
---|
| 69 | universal_char "\\"((u{hex_quad})|(U{hex_quad}{2})) |
---|
| 70 | |
---|
[8c17ab0] | 71 | // identifier, GCC: $ in identifier |
---|
[51b7345] | 72 | identifier ([a-zA-Z_$]|{universal_char})([0-9a-zA-Z_$]|{universal_char})* |
---|
| 73 | |
---|
[8c17ab0] | 74 | // quoted identifier |
---|
| 75 | quoted_identifier "`"{identifier}"`" |
---|
| 76 | |
---|
| 77 | // attribute identifier, GCC: $ in identifier |
---|
[51b7345] | 78 | attr_identifier "@"{identifier} |
---|
| 79 | |
---|
[8c17ab0] | 80 | // numeric constants, CFA: '_' in constant |
---|
[51b7345] | 81 | hex_quad {hex}{4} |
---|
| 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} |
---|
| 98 | floating_suffix "_"?[flFL] |
---|
| 99 | floating_constant (({fractional_constant}{exponent}?)|({decimal_digits}{exponent})){floating_suffix}? |
---|
| 100 | |
---|
| 101 | binary_exponent "_"?[pP]"_"?[+-]?{decimal_digits} |
---|
| 102 | hex_fractional_constant ({hex_digits}?"."{hex_digits})|({hex_digits}".") |
---|
| 103 | hex_floating_constant {hex_prefix}(({hex_fractional_constant}{binary_exponent})|({hex_digits}{binary_exponent})){floating_suffix}? |
---|
| 104 | |
---|
[8c17ab0] | 105 | // character escape sequence, GCC: \e => esc character |
---|
[51b7345] | 106 | simple_escape "\\"[abefnrtv'"?\\] |
---|
[8c17ab0] | 107 | // ' stop highlighting |
---|
[51b7345] | 108 | octal_escape "\\"{octal}{1,3} |
---|
| 109 | hex_escape "\\""x"{hex}+ |
---|
| 110 | escape_seq {simple_escape}|{octal_escape}|{hex_escape}|{universal_char} |
---|
| 111 | |
---|
[8c17ab0] | 112 | // display/white-space characters |
---|
[51b7345] | 113 | h_tab [\011] |
---|
| 114 | form_feed [\014] |
---|
| 115 | v_tab [\013] |
---|
| 116 | c_return [\015] |
---|
| 117 | h_white [ ]|{h_tab} |
---|
| 118 | |
---|
[8c17ab0] | 119 | // operators |
---|
[51b7345] | 120 | op_unary_only "~"|"!" |
---|
| 121 | op_unary_binary "+"|"-"|"*" |
---|
| 122 | op_unary_pre_post "++"|"--" |
---|
| 123 | op_unary {op_unary_only}|{op_unary_binary}|{op_unary_pre_post} |
---|
| 124 | |
---|
| 125 | op_binary_only "/"|"%"|"^"|"&"|"|"|"<"|">"|"="|"=="|"!="|"<<"|">>"|"<="|">="|"+="|"-="|"*="|"/="|"%="|"&="|"|="|"^="|"<<="|">>=" |
---|
| 126 | op_binary_over {op_unary_binary}|{op_binary_only} |
---|
| 127 | op_binary_not_over "?"|"->"|"&&"|"||" |
---|
| 128 | operator {op_unary_pre_post}|{op_binary_over}|{op_binary_not_over} |
---|
| 129 | |
---|
| 130 | %x COMMENT |
---|
[8c17ab0] | 131 | %x QUOTED |
---|
[51b7345] | 132 | |
---|
| 133 | %% |
---|
| 134 | /* line directives */ |
---|
| 135 | ^{h_white}*"#"{h_white}*[0-9]+{h_white}*["][^"\n]+["][^\n]*"\n" { |
---|
[8c17ab0] | 136 | /* " stop highlighting */ |
---|
[51b7345] | 137 | char *end_num; |
---|
| 138 | char *begin_string, *end_string; |
---|
| 139 | char *filename; |
---|
| 140 | long lineno, length; |
---|
| 141 | lineno = strtol( yytext + 1, &end_num, 0 ); |
---|
| 142 | begin_string = strchr( end_num, '"' ); |
---|
| 143 | if( begin_string ) { |
---|
| 144 | end_string = strchr( begin_string + 1, '"' ); |
---|
| 145 | if( end_string ) { |
---|
| 146 | length = end_string - begin_string - 1; |
---|
| 147 | filename = new char[ length + 1 ]; |
---|
| 148 | memcpy( filename, begin_string + 1, length ); |
---|
| 149 | filename[ length ] = '\0'; |
---|
| 150 | //std::cout << "file " << filename << " line " << lineno << std::endl; |
---|
| 151 | yylineno = lineno; |
---|
| 152 | yyfilename = filename; |
---|
| 153 | } |
---|
| 154 | } |
---|
| 155 | } |
---|
| 156 | |
---|
| 157 | /* ignore preprocessor directives (for now) */ |
---|
| 158 | ^{h_white}*"#"[^\n]*"\n" ; |
---|
| 159 | |
---|
| 160 | /* ignore C style comments */ |
---|
| 161 | "/*" {BEGIN COMMENT;} |
---|
| 162 | <COMMENT>.|\n ; |
---|
| 163 | <COMMENT>"*/" {BEGIN 0;} |
---|
| 164 | |
---|
| 165 | /* ignore C++ style comments */ |
---|
| 166 | "//"[^\n]*"\n" ; |
---|
| 167 | |
---|
| 168 | /* ignore whitespace */ |
---|
| 169 | {h_white}+ {WHITE_RETURN(' ');} |
---|
| 170 | ({v_tab}|{c_return}|{form_feed})+ {WHITE_RETURN(' ');} |
---|
| 171 | ({h_white}|{v_tab}|{c_return}|{form_feed})*"\n" {NEWLINE_RETURN();} |
---|
| 172 | |
---|
| 173 | /* keywords */ |
---|
| 174 | __alignof {KEYWORD_RETURN(ALIGNOF);} /* GCC */ |
---|
| 175 | __alignof__ {KEYWORD_RETURN(ALIGNOF);} /* GCC */ |
---|
| 176 | asm {KEYWORD_RETURN(ASM);} |
---|
| 177 | __asm {KEYWORD_RETURN(ASM);} /* GCC */ |
---|
| 178 | __asm__ {KEYWORD_RETURN(ASM);} /* GCC */ |
---|
| 179 | __attribute {KEYWORD_RETURN(ATTRIBUTE);} /* GCC */ |
---|
| 180 | __attribute__ {KEYWORD_RETURN(ATTRIBUTE);} /* GCC */ |
---|
| 181 | auto {KEYWORD_RETURN(AUTO);} |
---|
| 182 | _Bool {KEYWORD_RETURN(BOOL);} /* ANSI99 */ |
---|
| 183 | break {KEYWORD_RETURN(BREAK);} |
---|
| 184 | case {KEYWORD_RETURN(CASE);} |
---|
| 185 | catch {KEYWORD_RETURN(CATCH);} /* CFA */ |
---|
| 186 | char {KEYWORD_RETURN(CHAR);} |
---|
[8c17ab0] | 187 | choose {KEYWORD_RETURN(CHOOSE);} /* CFA */ |
---|
[51b7345] | 188 | _Complex {KEYWORD_RETURN(COMPLEX);} /* ANSI99 */ |
---|
| 189 | __complex {KEYWORD_RETURN(COMPLEX);} /* GCC */ |
---|
| 190 | __complex__ {KEYWORD_RETURN(COMPLEX);} /* GCC */ |
---|
| 191 | const {KEYWORD_RETURN(CONST);} |
---|
| 192 | __const {KEYWORD_RETURN(CONST);} /* GCC */ |
---|
| 193 | __const__ {KEYWORD_RETURN(CONST);} /* GCC */ |
---|
[8c17ab0] | 194 | context {KEYWORD_RETURN(CONTEXT);} /* CFA */ |
---|
[51b7345] | 195 | continue {KEYWORD_RETURN(CONTINUE);} |
---|
| 196 | default {KEYWORD_RETURN(DEFAULT);} |
---|
| 197 | do {KEYWORD_RETURN(DO);} |
---|
| 198 | double {KEYWORD_RETURN(DOUBLE);} |
---|
[8c17ab0] | 199 | dtype {KEYWORD_RETURN(DTYPE);} /* CFA */ |
---|
[51b7345] | 200 | else {KEYWORD_RETURN(ELSE);} |
---|
| 201 | enum {KEYWORD_RETURN(ENUM);} |
---|
| 202 | __extension__ {KEYWORD_RETURN(EXTENSION);} /* GCC */ |
---|
| 203 | extern {KEYWORD_RETURN(EXTERN);} |
---|
[8c17ab0] | 204 | fallthru {KEYWORD_RETURN(FALLTHRU);} /* CFA */ |
---|
[51b7345] | 205 | finally {KEYWORD_RETURN(FINALLY);} /* CFA */ |
---|
| 206 | float {KEYWORD_RETURN(FLOAT);} |
---|
| 207 | for {KEYWORD_RETURN(FOR);} |
---|
[8c17ab0] | 208 | forall {KEYWORD_RETURN(FORALL);} /* CFA */ |
---|
[51b7345] | 209 | fortran {KEYWORD_RETURN(FORTRAN);} |
---|
[8c17ab0] | 210 | ftype {KEYWORD_RETURN(FTYPE);} /* CFA */ |
---|
[51b7345] | 211 | goto {KEYWORD_RETURN(GOTO);} |
---|
| 212 | if {KEYWORD_RETURN(IF);} |
---|
| 213 | _Imaginary {KEYWORD_RETURN(IMAGINARY);} /* ANSI99 */ |
---|
| 214 | __imag {KEYWORD_RETURN(IMAGINARY);} /* GCC */ |
---|
| 215 | __imag__ {KEYWORD_RETURN(IMAGINARY);} /* GCC */ |
---|
| 216 | inline {KEYWORD_RETURN(INLINE);} /* ANSI99 */ |
---|
| 217 | __inline {KEYWORD_RETURN(INLINE);} /* GCC */ |
---|
| 218 | __inline__ {KEYWORD_RETURN(INLINE);} /* GCC */ |
---|
| 219 | int {KEYWORD_RETURN(INT);} |
---|
| 220 | __label__ {KEYWORD_RETURN(LABEL);} /* GCC */ |
---|
| 221 | long {KEYWORD_RETURN(LONG);} |
---|
[8c17ab0] | 222 | lvalue {KEYWORD_RETURN(LVALUE);} /* CFA */ |
---|
[51b7345] | 223 | register {KEYWORD_RETURN(REGISTER);} |
---|
| 224 | restrict {KEYWORD_RETURN(RESTRICT);} /* ANSI99 */ |
---|
| 225 | __restrict {KEYWORD_RETURN(RESTRICT);} /* GCC */ |
---|
| 226 | __restrict__ {KEYWORD_RETURN(RESTRICT);} /* GCC */ |
---|
| 227 | return {KEYWORD_RETURN(RETURN);} |
---|
| 228 | short {KEYWORD_RETURN(SHORT);} |
---|
| 229 | signed {KEYWORD_RETURN(SIGNED);} |
---|
| 230 | __signed {KEYWORD_RETURN(SIGNED);} /* GCC */ |
---|
| 231 | __signed__ {KEYWORD_RETURN(SIGNED);} /* GCC */ |
---|
| 232 | sizeof {KEYWORD_RETURN(SIZEOF);} |
---|
| 233 | static {KEYWORD_RETURN(STATIC);} |
---|
| 234 | struct {KEYWORD_RETURN(STRUCT);} |
---|
| 235 | switch {KEYWORD_RETURN(SWITCH);} |
---|
| 236 | throw {KEYWORD_RETURN(THROW);} /* CFA */ |
---|
| 237 | try {KEYWORD_RETURN(TRY);} /* CFA */ |
---|
[8c17ab0] | 238 | type {KEYWORD_RETURN(TYPE);} /* CFA */ |
---|
[51b7345] | 239 | typedef {KEYWORD_RETURN(TYPEDEF);} |
---|
| 240 | typeof {KEYWORD_RETURN(TYPEOF);} /* GCC */ |
---|
| 241 | __typeof {KEYWORD_RETURN(TYPEOF);} /* GCC */ |
---|
| 242 | __typeof__ {KEYWORD_RETURN(TYPEOF);} /* GCC */ |
---|
| 243 | union {KEYWORD_RETURN(UNION);} |
---|
| 244 | unsigned {KEYWORD_RETURN(UNSIGNED);} |
---|
| 245 | void {KEYWORD_RETURN(VOID);} |
---|
| 246 | volatile {KEYWORD_RETURN(VOLATILE);} |
---|
| 247 | __volatile {KEYWORD_RETURN(VOLATILE);} /* GCC */ |
---|
| 248 | __volatile__ {KEYWORD_RETURN(VOLATILE);} /* GCC */ |
---|
| 249 | while {KEYWORD_RETURN(WHILE);} |
---|
| 250 | |
---|
| 251 | /* identifier */ |
---|
| 252 | {identifier} {IDENTIFIER_RETURN();} |
---|
| 253 | {attr_identifier} {ATTRIBUTE_RETURN();} |
---|
[8c17ab0] | 254 | "`" {BEGIN QUOTED;} |
---|
| 255 | <QUOTED>{identifier} {IDENTIFIER_RETURN();} |
---|
| 256 | <QUOTED>"`" {BEGIN 0;} |
---|
[51b7345] | 257 | |
---|
| 258 | /* numeric constants */ |
---|
| 259 | "0" {NUMERIC_RETURN(ZERO);} /* CFA */ |
---|
| 260 | "1" {NUMERIC_RETURN(ONE);} /* CFA */ |
---|
| 261 | {decimal_constant} {NUMERIC_RETURN(INTEGERconstant);} |
---|
| 262 | {octal_constant} {NUMERIC_RETURN(INTEGERconstant);} |
---|
| 263 | {hex_constant} {NUMERIC_RETURN(INTEGERconstant);} |
---|
| 264 | {floating_constant} {NUMERIC_RETURN(FLOATINGconstant);} |
---|
| 265 | {hex_floating_constant} {NUMERIC_RETURN(FLOATINGconstant);} |
---|
| 266 | |
---|
| 267 | /* character constant, allows empty value */ |
---|
| 268 | "L"?[']([^'\\\n]|{escape_seq})*['] {RETURN_VAL(CHARACTERconstant);} |
---|
[8c17ab0] | 269 | /* ' stop highlighting */ |
---|
[51b7345] | 270 | |
---|
| 271 | /* string constant */ |
---|
| 272 | "L"?["]([^"\\\n]|{escape_seq})*["] {RETURN_VAL(STRINGliteral);} |
---|
[8c17ab0] | 273 | /* " stop highlighting */ |
---|
[51b7345] | 274 | |
---|
| 275 | /* punctuation */ |
---|
| 276 | "[" {ASCIIOP_RETURN();} |
---|
| 277 | "]" {ASCIIOP_RETURN();} |
---|
| 278 | "(" {ASCIIOP_RETURN();} |
---|
| 279 | ")" {ASCIIOP_RETURN();} |
---|
| 280 | "{" {ASCIIOP_RETURN();} |
---|
| 281 | "}" {ASCIIOP_RETURN();} |
---|
| 282 | "," {ASCIIOP_RETURN();} /* also operator */ |
---|
| 283 | ":" {ASCIIOP_RETURN();} |
---|
| 284 | ";" {ASCIIOP_RETURN();} |
---|
| 285 | "." {ASCIIOP_RETURN();} /* also operator */ |
---|
| 286 | "..." {NAMEDOP_RETURN(ELLIPSIS);} |
---|
| 287 | |
---|
| 288 | /* alternative ANSI99 brackets, "<:" & "<:<:" handled by preprocessor */ |
---|
| 289 | "<:" {RETURN_VAL('[');} |
---|
| 290 | ":>" {RETURN_VAL(']');} |
---|
| 291 | "<%" {RETURN_VAL('{');} |
---|
| 292 | "%>" {RETURN_VAL('}');} |
---|
| 293 | |
---|
| 294 | /* operators */ |
---|
| 295 | "!" {ASCIIOP_RETURN();} |
---|
| 296 | "+" {ASCIIOP_RETURN();} |
---|
| 297 | "-" {ASCIIOP_RETURN();} |
---|
| 298 | "*" {ASCIIOP_RETURN();} |
---|
| 299 | "/" {ASCIIOP_RETURN();} |
---|
| 300 | "%" {ASCIIOP_RETURN();} |
---|
| 301 | "^" {ASCIIOP_RETURN();} |
---|
| 302 | "~" {ASCIIOP_RETURN();} |
---|
| 303 | "&" {ASCIIOP_RETURN();} |
---|
| 304 | "|" {ASCIIOP_RETURN();} |
---|
| 305 | "<" {ASCIIOP_RETURN();} |
---|
| 306 | ">" {ASCIIOP_RETURN();} |
---|
| 307 | "=" {ASCIIOP_RETURN();} |
---|
| 308 | "?" {ASCIIOP_RETURN();} |
---|
| 309 | |
---|
| 310 | "++" {NAMEDOP_RETURN(ICR);} |
---|
| 311 | "--" {NAMEDOP_RETURN(DECR);} |
---|
| 312 | "==" {NAMEDOP_RETURN(EQ);} |
---|
| 313 | "!=" {NAMEDOP_RETURN(NE);} |
---|
| 314 | "<<" {NAMEDOP_RETURN(LS);} |
---|
| 315 | ">>" {NAMEDOP_RETURN(RS);} |
---|
| 316 | "<=" {NAMEDOP_RETURN(LE);} |
---|
| 317 | ">=" {NAMEDOP_RETURN(GE);} |
---|
| 318 | "&&" {NAMEDOP_RETURN(ANDAND);} |
---|
| 319 | "||" {NAMEDOP_RETURN(OROR);} |
---|
| 320 | "->" {NAMEDOP_RETURN(ARROW);} |
---|
| 321 | "+=" {NAMEDOP_RETURN(PLUSassign);} |
---|
| 322 | "-=" {NAMEDOP_RETURN(MINUSassign);} |
---|
| 323 | "*=" {NAMEDOP_RETURN(MULTassign);} |
---|
| 324 | "/=" {NAMEDOP_RETURN(DIVassign);} |
---|
| 325 | "%=" {NAMEDOP_RETURN(MODassign);} |
---|
| 326 | "&=" {NAMEDOP_RETURN(ANDassign);} |
---|
| 327 | "|=" {NAMEDOP_RETURN(ORassign);} |
---|
| 328 | "^=" {NAMEDOP_RETURN(ERassign);} |
---|
| 329 | "<<=" {NAMEDOP_RETURN(LSassign);} |
---|
| 330 | ">>=" {NAMEDOP_RETURN(RSassign);} |
---|
| 331 | |
---|
| 332 | /* CFA, operator identifier */ |
---|
| 333 | {op_unary}"?" {IDENTIFIER_RETURN();} /* unary */ |
---|
| 334 | "?"({op_unary_pre_post}|"()"|"[?]") {IDENTIFIER_RETURN();} |
---|
| 335 | "?"{op_binary_over}"?" {IDENTIFIER_RETURN();} /* binary */ |
---|
| 336 | /* |
---|
| 337 | This rule handles ambiguous cases with operator identifiers, e.g., "int *?*?()", where the |
---|
| 338 | string "*?*?" can be lexed as "*"/"?*?" or "*?"/"*?". Since it is common practise to put |
---|
| 339 | a unary operator juxtaposed to an identifier, e.g., "*i", users will be annoyed if they |
---|
| 340 | cannot do this with respect to operator identifiers. Even with this special hack, there |
---|
| 341 | are 5 general cases that cannot be handled. The first case is for the function-call |
---|
| 342 | identifier "?()": |
---|
| 343 | |
---|
| 344 | int * ?()(); // declaration: space required after '*' |
---|
| 345 | * ?()(); // expression: space required after '*' |
---|
| 346 | |
---|
| 347 | Without the space, the string "*?()" is ambiguous without N character look ahead; it |
---|
| 348 | requires scanning ahead to determine if there is a '(', which is the start of an |
---|
| 349 | argument/parameter list. |
---|
| 350 | |
---|
| 351 | The 4 remaining cases occur in expressions: |
---|
| 352 | |
---|
| 353 | i++?i:0; // space required before '?' |
---|
| 354 | i--?i:0; // space required before '?' |
---|
| 355 | i?++i:0; // space required after '?' |
---|
| 356 | i?--i:0; // space required after '?' |
---|
| 357 | |
---|
| 358 | In the first two cases, the string "i++?" is ambiguous, where this string can be lexed as |
---|
| 359 | "i"/"++?" or "i++"/"?"; it requires scanning ahead to determine if there is a '(', which |
---|
| 360 | is the start of an argument list. In the second two cases, the string "?++x" is |
---|
| 361 | ambiguous, where this string can be lexed as "?++"/"x" or "?"/"++x"; it requires scanning |
---|
| 362 | ahead to determine if there is a '(', which is the start of an argument list. |
---|
| 363 | */ |
---|
| 364 | {op_unary}"?"(({op_unary_pre_post}|"[?]")|({op_binary_over}"?")) { |
---|
| 365 | // 1 or 2 character unary operator ? |
---|
| 366 | int i = yytext[1] == '?' ? 1 : 2; |
---|
| 367 | yyless( i ); /* put back characters up to first '?' */ |
---|
| 368 | if ( i > 1 ) { |
---|
| 369 | NAMEDOP_RETURN( yytext[0] == '+' ? ICR : DECR ); |
---|
| 370 | } else { |
---|
| 371 | ASCIIOP_RETURN(); |
---|
| 372 | } // if |
---|
| 373 | } |
---|
| 374 | |
---|
| 375 | /* unknown characters */ |
---|
| 376 | . {printf("unknown character(s):\"%s\" on line %d\n", yytext, yylineno);} |
---|
| 377 | |
---|
| 378 | %% |
---|
| 379 | |
---|
| 380 | |
---|
[8c17ab0] | 381 | // Local Variables: |
---|
| 382 | // fill-column: 100 |
---|
| 383 | // compile-command: "make" |
---|
| 384 | // End: |
---|