+ What is tinylex?
   A tiny lexical analyser generator


+ How to implement?
   I refer to Allen Holub's book 'Compiler design in C'
    and write it by myself.


+ Format of the input file
  (see test/colour.l for example, which is a C syntax higlighter):

  %{
    < code block for definition or macro >
  %}
    < Macro Definition: macroname macrotext     >
    < e.g:              digit     [0-9]         >
    < recursive macro definition is not allowed.>
  %%
    < Rules: regularexp  action string          >
    < e.g:   {digit}+    printf("%d", yytext);  >
    < only one-line action string is allowed.   >
  %%
    < code block for main function >


+ Usage:
  compile:
    # make
      [generate tinylex and egrep_like ]
    # ./tinylex -p lex.yy.part.c {source script}.l -o {generated ouput}.c

  test:
    # make test
      [see the output information]

  debug:
    # make debug  
      [generate many debug programes, such as nfa]
    # ./nfa test/common_test.l
      [output NFAS information according to
       common_test.l script (regular expresion for testing) ]


+ TODO:
   1. bugfix:
      using `grep -C 2 -n FIXME *.c` to get bug information
   2. make tinylex compatible with flex/lex.
      (Tinylex is only subset of flex/lex now.
       And many auxiliary functions or flags aren't supported,
       such as yywrap/yymore/yyrestart)
   3. support multi-line accept action string
      (Maybe I need a internal C parser.)
   4. support recursive macro definition


+ Author:
   Xiaochen Wang <wangxiaochen0@gmail.com>