fickle is a Tcl utility that generates Tcl code, much like flex does for C code. From the README:
This is a scanner generator program, much like flex(1) is to C. If you have no desire to author Tcl programs, particularly those that manipulate text, fickle is not for you. A passing knowledge of flex or some other lex-like program would be useful, as that fickle uses nearly identical syntax and commands as flex. Two good references are the flex man page and the O'Reilly book 'lex & yacc' by Levine, Mason, and Brown.
(Complete README[L1 ]).
The fickle package comes with a bunch of example files, derived from lex & yacc[L2 ].
Download fickle 1.00 from http://tcl.jtang.org/fickle/fickle-1.00.tar.gz .
fickle is protected by the GNU general public license.
Invoke fickle before running the program, much akin to flex:
> tclsh fickle.tcl foo.fcl > tclsh foo.tcl
whereas with flex it would be:
> flex foo.f > gcc -o foo lex.yy.c -lfl > ./foo
For comparison purposes, here's a fickle specification file to match some English verbs:
%{
#!/usr/bin/tclsh
# Recognizes various English verbs in sentences.
# This is based upon example 'ch1-02.l' from "lex & yacc" by John
# R. Levine, Tony Mason, and Doug Brown (by O'Reilly & Associates, ISBN
# 1-56592-000-7). For more information on using lex and yacc, see
# http://www.oreilly.com/catalog/lex/.
%}
%%
[\t ]+ # ignore whitespace
is |
am |
are |
were |
was |
be |
being |
been |
do |
does |
did |
will puts "$yytext: is a verb"
[a-zA-Z]+ puts "$yytext: is not a verb"
.|\n ECHO ;# normal default anyway
%%
yylexAnd the equivalent flex version:
%{
/*
* this sample demonstrates (very) simple recognition:
* a verb/not a verb. this example derived from 'ch1-02.l'.
*/
%}
%%
[\t ]+ /* ignore whitespace */
is |
am |
are |
were |
was |
be |
being |
been |
do |
does |
did |
will { printf ("%s: is a verb\n", yytext); }
[a-zA-Z]+ { printf ("%s: is not a verb\n", yytext); }
.|\n { ECHO; /* normal default anyway */ }
%%
main()
{
yylex();
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