crowbar.l

%{
#include <stdio.h>
#include <string.h>
#include "DBG.h"
#include "crowbar.h"
#include "y.tab.h"

int
yywrap(void)
{
  return 1;
}

static void
increment_line_number(void)
{
  crb_get_current_interpreter()->current_line_number++;
}
%}

%start COMMENT STRING_LITERAL_STATE
%%
<INITIAL>"function" return FUNCTION;
<INITIAL>"if"       return IF;
<INITIAL>"else"     return ELSE;
<INITIAL>"elsif"    return ELSIF;
<INITIAL>"while"    return WHILE;
<INITIAL>"for"      return FOR;
<INITIAL>"return"   return RETURN_T;
<INITIAL>"break"    return BREAK;
<INITIAL>"continue" return CONTINUE;
<INITIAL>"null"     return NULL_T;
<INITIAL>"true"     return TRUE_T;
<INITIAL>"false"    return FALSE_T;
<INITIAL>"global"   return GLOBAL_T;
<INITIAL>"("        return LP;
<INITIAL>")"        return RP;
<INITIAL>"{"        return LC;
<INITIAL>"}"        return RC;
<INITIAL>";"        return SEMICOLON;
<INITIAL>","        return COMMA;
<INITIAL>"&&"       return LOGICAL_AND;
<INITIAL>"||"       return LOGICAL_OR;
<INITIAL>"="        return ASSIGN;
<INITIAL>"=="       return EQ;
<INITIAL>"!="       return NE;
<INITIAL>">"        return GT;
<INITIAL>">="       return GE;
<INITIAL>"<"        return LT;
<INITIAL>"<="       return LE;
<INITIAL>"+"        return ADD;
<INITIAL>"-"        return SUB;
<INITIAL>"*"        return MUL;
<INITIAL>"/"        return DIV;
<INITIAL>"%"        return MOD;
<INITIAL>[A-Za-z_][A-Za-z_0-9]* {
  yylval.identifier = crb_create_identifier(yytext);
  return IDENTIFIER;
}
<INITIAL>([1-9][0-9]*)|"0" {
  Expression *expression = crb_alloc_expression(INT_EXPRESSION);
  sscanf(yytext, "%d", &expression->u.int_value);
  yylval.expression = expression;
  return INT_LITERAL;
}
<INITIAL>[0-9]+\.[0-9]+ {
  Expression *Expression = crb_alloc_expression(DOUBLE_EXPRESSION);
  sscanf(yytext, "%lf", &expression->u.double_value);
  yylval.Expression = expression;

  return DOUBLE_LITERAL;
}
<INITIAL>\" {
  crb_open_string_literal();
  BEGIN STRING_LITERAL_STATE;
}

# skip whitespace
<INITIAL>[ \t] ;
<INITIAL>\n {increment_line_number();}

# 所有其它的字符都报错
<INITIAL>. {
  char buf[LINE_BUF_SIZE];

  if (isprint(yytext[0])) {
	buf[0] = yytext[0];
	buf[1] = '\0';
  } else {
	sprintf(buf, "0x%02x", (unsigned char)yytext[0]);
  }

  crb_compile_error(CHARACTER_INVALID_ERR,
					STRING_MESSAGE_ARGUMENT,
					"bad_char",
					buf,
					MESSAGE_ARGUMENT_END);
}

<COMMENT>\n {
  increment_line_number();
  BEGIN INITIAL;
}

<COMMENT>. ;

<STRING_LITERAL_STATE>\"  {
  Expression *Expression = crb_alloc_expression(STRING_EXPRESSION);
  Expression->u.string_value = crb_close_string_literal();
  yylval.expression = expression;
  BEGIN INITIAL;
  return STRING_LITERAL;
}

<STRING_LITERAL_STATE>\n {
  crb_add_string_literal('\n');
  increment_line_number();
}

<STRING_LITERAL_STATE>\\\" crb_add_string_literal('"');
<STRING_LITERAL_STATE>\\n crb_add_string_literal('\n');
<STRING_LITERAL_STATE>\\t crb_add_string_literal('\t');
<STRING_LITERAL_STATE>\\\\ crb_add_string_literal('\\');
<STRING_LITERAL_STATE>. crb_add_string_literal(yytext[0]);
%%