javascript - I have a parser to make, i'd like to learn proper parsing -

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i want parse text javascript. syntax want parse markup language. language has 2 main kind of markup:

$f56

mean following characters of color #f56. until following $ 3 hex char using color.

$i

mean until following $z (closing tag) text in italic. other 1 letter tags.

so language composed of 3 character long hexa tags color , 1 letter long tags.

i can craft ugly parse text, storing char position , current status of tags (formatting , color) i'd learn proper parsing. give me few tips/principle make clean parser language ?

if know antlr might intrested in exploring http://www.antlr.org/wiki/display/antlr3/antlr3javascripttarget , generates javascript lexers , parsers

if set target language javascript

grammer t.g

grammar t; options {     language=javascript;     [other options] } ... ...

parser.html 

<script type="text/javascript" src="lib/antlr3-all-min.js"></script> <script type="text/javascript" src="tlexer.js"></script> <script type="text/javascript" src="tparser.js"></script> <script type="text/javascript" src="twalker.js"></script>  <script type="text/javascript"> var input = "...what want feed parser...",      cstream = new org.antlr.runtime.antlrstringstream(input),      lexer = new tlexer(cstream),      tstream = new org.antlr.runtime.commontokenstream(lexer),      parser = new tparser(tstream),      r = parser.entry_rule();  var nodes = new org.antlr.runtime.tree.commontreenodestream(r.gettree()); nodes.settokenstream(tstream); var walker = new twalker(nodes); walker.tree_entry_rule(); </script>

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