location of filter engine in src

[Steve Lime]

So you want to add a modulus operator correct? (I thought it existed but I was wrong) To do that is pretty straight forward you have to edit one file and recompile:

  - mapparser.y -> this is the Bison/YACC parser grammar, the '%' operator needs to be added to the section that defines operator precedence, and down in the math_exp syntax session

I don't have my reference manual handy but looking through a perl manual I see the '%' operator at the same level as '*' and '/' so in the precedence section. So you can change the line:

%left '*' '/'

to

%left '*' '/' '%'

and change:

| math_exp '*' math_exp { $$ = $1 * $3; }

to

| math_exp '*' math_exp { $$ = $1 * $3; }
| math_exp '%' math_exp { $$ = $1 % $3; }

or something close to this. Lemme know if it works and I'll patch 4.8 and 4.9.

Steve

>>> Charlton Purvis <cplist at EARTHLINK.NET> 01/27/06 12:04 PM >>>
Hi, folks:

I'd like to modify the filter to execute modulus in addition to everything
it already does (http://mapserver.gis.umn.edu/docs/howto/msexpressions).
I'm looking through the code right now, but if somebody knows off the top of
their head where to point me, that would be great.

Thanks,

Charlton