Re: Syntax Highlighting and Lexical Analysis

> Syntax highlighing ?


Use something like 'flex' which will recongize all your base lexems
(words, ponctuations...) then use it on a per line basys (i don't
remenber if lex do that easily, but it must be possible) and in the
return of each function associated with a regular expression (which
describes your lexem) your return the number of character making up
the expression, and a code then you deduce a color from the code (you
can use the color code directly, but if you want the colors to be
parameterized, use the code as lookup index in a color table that the
user fills with a great interface :)


then you just have to do for each line :
        for each (code,nb_char) group
                set the color
                print the nb_char next character in the string
        next


if your lexer stop before the of the file : color the rest of the line an
red by example to show the user he has made a mistake.


you can use the 'above' context (lines before the one you colorize) if you
use comments as /* */
(VC++ uses the 100 previous lines for is context by default).


wish it helped you
Armel ASSELIN

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