What's wrong with my lex and yacc program?

Discussion in 'C Programming' started by cylin, Jan 7, 2004.

  1. cylin

    cylin Guest

    Dear all,

    I am a newbie using lex and yacc.
    I really don't know what's wrong with my code, because the output is not
    what I want.
    My yacc rules don't match, and yylex seems just read only one line of the
    text file.

    Please help...thx.

    test file:
    SLICE 1,17
    VERSION : 3.2.5

    #ifndef YYERRCODE
    #define YYERRCODE 256

    #define SLICE 257
    #define VERSION 258
    #define INTEGER 259
    typedef union {
    int iInteger;
    char* szRecord;
    } YYSTYPE;
    extern YYSTYPE yylval;

    #include "test.h"

    comment "*".*
    whitespace [ \t\r\n]+


    {whitespace} ;
    {comment} ;
    SLICE {yylval.szRecord=strdup(yytext);printf("In lex %s
    ",yylval.szRecord);return SLICE;}
    VERSION {yylval.szRecord=strdup(yytext);printf("In lex %s
    ",yylval.szRecord);return VERSION;}
    [0-9]+ {yylval.iInteger=atoi(yytext);printf("In lex..%d
    ",yylval.iInteger);return INTEGER;}
    .. ;


    /* MEBES job file parser */
    #include <stdio.h>

    %union {
    int iInteger;
    char* szRecord;

    %token <szRecord> SLICE VERSION
    %token <iInteger> INTEGER


    test : SLICE {printf("Got SLICE\n");}
    | SLICE INTEGER ',' INTEGER {printf("In SLICE,no1=%d,no2=%d\n",$2,$4);}
    test2 : VERSION {printf("%s \n",$1);}


    extern FILE *yyin;

    int main(int argc,char** argv)
    if (yyin) {
    while (!feof(yyin)) {
    return 0;
    else {
    return -1;

    yyerror(char* errmsg)
    cylin, Jan 7, 2004
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  2. Ben Pfaff

    Ben Pfaff Guest

    [c.l.c redirection guidance] Re: What's wrong with my lex and yacc program?

    "cylin" <> writes:

    > I am a newbie using lex and yacc.

    Your question is outside the domain of comp.lang.c, which discusses
    only the standard C programming language, including the standard C
    library. This is a remarkably narrow topic compared to what many
    people expect.

    For your convenience, the list below contains topics that are not
    on-topic for comp.lang.c, and suggests newsgroups for you to explore
    if you have questions about these topics. Please do observe proper
    netiquette before posting to any of these newsgroups. In particular,
    you should read the group's charter and FAQ, if any (FAQs are
    available from www.faqs.org and other sources). If those fail to
    answer your question then you should browse through at least two weeks
    of recent articles to make sure that your question has not already
    been answered.

    * OS-specific questions, such as how to clear the screen,
    access the network, list the files in a directory, or read
    "piped" output from a subprocess. These questions should be
    directed to OS-specific newsgroups, such as
    comp.os.ms-windows.programmer.misc, comp.unix.programmer, or

    * Compiler-specific questions, such as installation issues and
    locations of header files. Ask about these in
    compiler-specific newsgroups, such as gnu.gcc.help or
    comp.os.ms-windows.programmer.misc. Questions about writing
    compilers are appropriate in comp.compilers.

    * Processor-specific questions, such as questions about
    assembly and machine code. x86 questions are appropriate in
    comp.lang.asm.x86, embedded system processor questions may
    be appropriate in comp.arch.embedded.

    * ABI-specific questions, such as how to interface assembly
    code to C. These questions are both processor- and
    OS-specific and should typically be asked in OS-specific

    * Algorithms, except questions about C implementations of
    algorithms. "How do I implement algorithm X in C?" is not a
    question about a C implementation of an algorithm, it is a
    request for source code. Newsgroups comp.programming and
    comp.theory may be appropriate.

    * Making C interoperate with other languages. C has no
    facilities for such interoperation. These questions should
    be directed to system- or compiler-specific newsgroups. C++
    has features for interoperating with C, so consider
    comp.lang.c++ for such questions.

    * The C standard, as opposed to standard C. Questions about
    the C standard are best asked in comp.std.c.

    * C++. Please do not post or cross-post questions about C++
    to comp.lang.c. Ask C++ questions in C++ newsgroups, such
    as comp.lang.c++ or comp.lang.c++.moderated.

    * Test posts. Please test in a newsgroup meant for testing,
    such as alt.test.

    news.groups.questions is a good place to ask about the appropriate
    newsgroup for a given topic.

    "Some people *are* arrogant, and others read the FAQ."
    --Chris Dollin
    Ben Pfaff, Jan 7, 2004
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