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%{ /* -*- C++ -*- */
# include <cstdlib>
# include <cerrno>
# include <climits>
# include <string>
# include "calc++-driver.hh"
# include "calc++-parser.hh"
/* Work around an incompatibility in flex (at least versions
2.5.31 through 2.5.33): it generates code that does
not conform to C89. See Debian bug 333231
<http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333231>. */
# undef yywrap
# define yywrap() 1
/* By default yylex returns int, we use token_type.
Unfortunately yyterminate by default returns 0, which is
not of token_type. */
#define yyterminate() return token::END
%}
%option noyywrap nounput batch debug
id [a-zA-Z][a-zA-Z_0-9]*
int [0-9]+
blank [ \t]
%{
# define YY_USER_ACTION yylloc->columns (yyleng);
%}
%%
%{
yylloc->step ();
%}
{blank}+ yylloc->step ();
[\n]+ yylloc->lines (yyleng); yylloc->step ();
%{
typedef yy::calcxx_parser::token token;
%}
/* Convert ints to the actual type of tokens. */
[-+*/] return yy::calcxx_parser::token_type (yytext[0]);
":=" return token::ASSIGN;
{int} {
errno = 0;
long n = strtol (yytext, NULL, 10);
if (! (INT_MIN <= n && n <= INT_MAX && errno != ERANGE))
driver.error (*yylloc, "integer is out of range");
yylval->ival = n;
return token::NUMBER;
}
{id} yylval->sval = new std::string (yytext); return token::IDENTIFIER;
. driver.error (*yylloc, "invalid character");
%%
void
calcxx_driver::scan_begin ()
{
yy_flex_debug = trace_scanning;
if (file == "-")
yyin = stdin;
else if (!(yyin = fopen (file.c_str (), "r")))
{
error (std::string ("cannot open ") + file);
exit (1);
}
}
void
calcxx_driver::scan_end ()
{
fclose (yyin);
}
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