CS143-Lab/assignments/PA2/cool.flex
2023-03-18 16:23:33 +08:00

108 lines
2.3 KiB
Plaintext

%{
/*
* The scanner definition for COOL.
*/
/*
* Stuff enclosed in %{ %} in the first section is copied verbatim to the
* output, so headers and global definitions are placed here to be visible
* to the code in the file. Don't remove anything that was here initially
*/
#include <cool-parse.h>
#include <stringtab.h>
#include <utilities.h>
/* The compiler assumes these identifiers. */
#define yylval cool_yylval
#define yylex cool_yylex
/* Max size of string constants */
#define MAX_STR_CONST 1025
#define YY_NO_UNPUT /* keep g++ happy */
extern FILE *fin; /* we read from this file */
/* define YY_INPUT so we read from the FILE fin:
* This change makes it possible to use this scanner in
* the Cool compiler.
*/
#undef YY_INPUT
#define YY_INPUT(buf,result,max_size) \
if ( (result = fread( (char*)buf, sizeof(char), max_size, fin)) < 0) \
YY_FATAL_ERROR( "read() in flex scanner failed");
char string_buf[MAX_STR_CONST]; /* to assemble string constants */
char *string_buf_ptr;
extern int curr_lineno;
extern int verbose_flag;
extern YYSTYPE cool_yylval;
/*
* Add Your own definitions here
*/
%}
/*
* Define names for regular expressions here.
*/
DARROW =>
DIGIT [0-9]
DIGITS {DIGIT}+
/* */
/* Keywords Definition*/
/* Except for the constants true and false, keywords are case insensitive */
K_CLASS (?i:class)
K_ELSE (?i:else)
K_FI (?i:fi)
K_IF (?i:if)
K_IN (?i:in)
K_INHERITS (?i:inherits)
K_ISVOID (?i:isvoid)
K_LET (?i:let)
K_LOOP (?i:loop)
K_POOL (?i:pool)
K_THEN (?i:then)
K_WHILE (?i:while)
K_CASE (?i:case)
K_ESAC (?i:esac)
K_NEW (?i:new)
K_OF (?i:of)
K_NOT (?i:not)
/* the first letter of true/false must be lowercase; the trailing may be upper or lower case. */
K_TRUE t(?i:rue)
K_FALSE f(?i:alse)
%%
/*
* Nested comments
*/
/*
* The multiple-character operators.
*/
{DARROW} { return (DARROW); }
/*
* Keywords are case-insensitive except for the values true and false,
* which must begin with a lower-case letter.
*/
/*
* String constants (C syntax)
* Escape sequence \c is accepted for all characters c. Except for
* \n \t \b \f, the result is c.
*
*/
%%