flex与bison的学习

获取bison

http://www.gnu.org/software/bison

获取flex

http://flex.sourceforge.net/

本书的范例

ftp://ftp.iecc.com/pub/file/flexbison.zip

第一个Flex程序

fb1-1.l

/* Companion source 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 conditions and contact info. * $Header: /home/johnl/flnb/code/RCS/fb1-1.l,v 2.1 2009/11/08 02:53:18 johnl Exp $ */
/* fb1-1 just like unix wc */%{int chars = 0;int words = 0;int lines = 0;%}
%%
[a-zA-Z]+	{ words++; chars += strlen(yytext); }\n		{ chars++; lines++; }.		{ chars++; }
%% main(){  yylex();  printf("lines:%8d\nwords:%8d\nchars:%8d\n", lines, words, chars);}yywrap() { return 1; }

文件放置。

编译运行该文件

运行结果测试