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Win flex-bison 的官网http://sourceforge.net/projects/winflexbison/
Win flex-bison isa port Flex & Bison tools to the Windows platform
学习编译原理的朋友，都会看到书中提到的 lex& yacc或flex &bison工具组合。这两组工具在Unix,Linux,BSD上使用不会有太大的问题，但在Windows上使用通常需要安装MinGW+ (Msys或Msys2 )或者Cygwin。Win flex-bison 提供了flex &bison 在Windows平台上另外一种移植，不需要依赖 m4，生成的c文件可以用VC编译。
下面以 Win flex_bison 2.5.1和《flex &bison》第一章的简单计算器fb1-5为例，简单介绍如何使用。
首先从 http://sourceforge.net/projects/winflexbison/ 下载已经编译好的压缩文件 win_flex_bison-2.5.1.zip（不到700kb），
Update: 2014-01-04
Description
Win flex-bison is a windows port the Flex(the fast lexical analyser) and Bison (GNU parser generator). win_flex based onFlex version 2.5.37 source code and win_bisonbased on Bison version 2.7 and they depend on system libraries only.
UPDATE1: Bison version 3.0 available in Files section in win_flex_bison-2.5.zippackage.
UPDATE2: Now "winflexbison" available as package in Chocolatey (http://chocolatey.org/packages/winflexbison)
Win flex-bison WebSite
Categories
Libraries
License
GNUGeneral Public License version 3.0 (GPLv3)
解压到某一文件夹（如 winFlexBison），将这个文件夹增加到 path 环境变量中，就可以命令行使用了。
Bison规则描述文件 fb1-5.y
/* Companionsource code for "flex & bison", published by O'Reilly
* Media, ISBN 978-0-596-15597-1
* Copyright (c) 2009, Taughannock Networks.All rights reserved.
* See the README file for license conditionsand contact info.
* $Header: /home/johnl/flnb/code/RCS/fb1-5.y,v2.1 2009/11/08 02:53:18 johnl Exp $
*/
/* simplestversion of calculator */
%{
# include <stdio.h>
%}
/* declare tokens*/
%token NUMBER
%token ADD SUB MULDIV ABS
%token OP CP
%token EOL
%%
calclist: /*nothing */
| calclist exp EOL { printf("= %d\n>", $2); }
| calclist EOL { printf("> "); }/* blank line or a comment */
;
exp: factor
| exp ADD exp { $$ = $1 + $3; }
| exp SUB factor { $$ = $1 - $3; }
| exp ABS factor { $$ = $1 | $3; }
;
factor: term
| factor MUL term { $$ = $1 * $3; }
| factor DIV term { $$ = $1 / $3; }
;
term: NUMBER
| ABS term { $$ = $2 >= 0? $2 : - $2; }
| OP exp CP { $$ = $2; }
;
%%
main()
{
printf("> ");
yyparse();
}
yyerror(char *s)
{
fprintf(stderr, "error: %s\n", s);
}
Flex词法分析文件 fb1-5.l
/* Companionsource code for "flex & bison", published by O'Reilly
* Media, ISBN 978-0-596-15597-1
* Copyright (c) 2009, Taughannock Networks.All rights reserved.
* See the README file for license conditionsand contact info.
* $Header: /home/johnl/flnb/code/RCS/fb1-5.l,v2.1 2009/11/08 02:53:18 johnl Exp $
*/
/* recognizetokens for the calculator and print them out */
%{
# include"fb1-5.tab.h"
%}
%%
"+" { return ADD; }
"-" { return SUB; }
"*" { return MUL; }
"/" { return DIV; }
"|" { return ABS; }
"(" { return OP; }
")" { return CP; }
[0-9]+ { yylval = atoi(yytext); return NUMBER; }
\n { return EOL; }
"//".*
[ \t] { /* ignore white space */ }
. { yyerror("Mystery character%c\n", *yytext); }
%%手工运行以下命令
win_bison -d fb1-5.y
生成 fb1-5.tab.h 和fb1-5.tab.c 文件
win_flex --nounistdfb1-5.l 或 win_flex --wincompat fb1-5.l
生成 lex.yy.c 文件。--nounistd 和 –wincompat选项使生成的 lex.yy.c 不依赖<unistd.h> 可以用 VC 编译，否则就只能用 gcc 编译了。
为了项目管理方便可将 lex.yy.c 重命名为 fb1-5.c ，用 cl 手工编译
cl fb1-5.cfb1-5.tab.c libfl.a 或 cl fb1-5.c fb1-5.tab.c libfl.lib
生成 fb1-5.exe ，由于用到 yywrap() 需要链接 flex 的 libfl.a 库。用VC编译的话，可以将 libfl.a 重名为libfl.lib 更直观。
运行一下fb1-5.exe
你也可以建立一个MakeFile文件 makefile.mak
# Build a Simple Calc with fb1-5.y and fb1-5.l
!IF "$(OS)" == "Windows_NT"
NULL=
!ELSE
NULL=nul
!ENDIF
CC=cl
CFLAGS=/DNDEBUG /D_SCL_SECURE_NO_WARNINGS /O2 /W3
LD=link
LDFLAGS=/nologo
LIBS=libfl.lib
MOVE=move /Y
ALL : fb1-5.exe
CLEAN :
-@erase "*.obj"
-@erase "fb1-5.c"
-@erase "fb1-5.tab.c"
-@erase "fb1-5.tab.h"
-@erase "fb1-5.exe"
OBJS=\
fb1-5.obj \
fb1-5.tab.obj \
"fb1-5.tab.c" : fb1-5.y
if not exist "$@/$(NULL)" win_bison -d $**
"fb1-5.tab.h" : fb1-5.y
if not exist "$@/$(NULL)" win_bison -d $**
"fb1-5.c" : fb1-5.l
if not exist "$@/$(NULL)" win_flex --nounistd $** && $(MOVE) lex.yy.c $@
"fb1-5.exe" : $(OBJS)
$(LD) $(LDFLAGS) /out:$@ $** $(LIBS)
"fb1-5.obj" : fb1-5.c fb1-5.tab.h
$(CC) $(CFLAGS) /c fb1-5.c
"fb1-5.tab.obj" : fb1-5.tab.c fb1-5.tab.h
$(CC) $(CFLAGS) /c fb1-5.tab.c
用 nmake /f makefile.mak
来构建。
另外一个国外图文并茂的教程为 Using flex andbison in MSVC++
http://www.di-mgt.com.au/flex_and_bison_in_msvc.html
本文就是从那演化来的。
libfl.a （ v2.5.37 ）可以从http://pan.baidu.com/s/1eQcKMgM下载；或从 GnuWin ，Msys , Msys2 中提取。