librelist archives

Lexer macros don't seem to work

From:

Dan Rumney

Date:

2010-03-12 @ 15:53

Hi,

I've been playing with JISON for a while now: great piece of software.

Problem is, I've hit a snag. I have the following LEX:

NUM    [0-9]+("."[0-9]+)?

%%
(
\d+\s*"'"\s*\d+\s*"\""\s*\d+\s*"s"
|\d+\s*"'"\s*\d+\s*"\""\s*
|\d+\s*"\""\s*\d+\s*"s"
|\d+\s*"'"\s*
|\d+\s*"\""\s*
|\d+\s*"s"
)
  {return 'FIS';}
{NUM}\b  {return 'NUMBER';}
\s+                   {/* skip whitespace */}
"*"                   {return '*';}
"/"                   {return '/';}
"-"                   {return '-';}
"+"                   {return '+';}
"("                   {return '(';}
")"                   {return ')';}
<<EOF>>               {return 'EOF';}

%%

When I run JISON, it doesn't complain or anything, but when I take a 
look at the generated code, I find:

lexer.rules = 

[/^(\d+\s*'\s*\d+\s*"\s*\d+\s*s|\d+\s*'\s*\d+\s*"\s*|\d+\s*"\s*\d+\s*s|\d+\s*'\s*|\d+\s*"\s*|\d+\s*s)/,/^{NUM}\b\b/,/^\s+/,/^\*/,/^\//,/^-/,/^\+/,/^\(/,/^\)/,/^$/]


You'll see that the macro, NUM, hasn't been expanded.

I invoked JISON like so:

narwhal bin/jison fisCalc.jison fisCalc.jisonlex

Do I need to feed it some extra parameters in order to expand macros? Or 
is there something wrong with me LEX?

Thanks,

Dan

On Fri, Mar 12, 2010 at 10:53 AM, Dan Rumney <danrumney@warpmail.net> wrote:

> Hi,
> ....
>
> You'll see that the macro, NUM, hasn't been expanded.
>
> I invoked JISON like so:
>
> narwhal bin/jison fisCalc.jison fisCalc.jisonlex
>
> Do I need to feed it some extra parameters in order to expand macros? Or
> is there something wrong with me LEX?
>
> Thanks,
>
> Dan
>

On the contrary, you have done nothing wrong Dan. This seems to be an error
in my jisonlex parser. I create an array tuple ([key, regex]) when I
*really* meant to create a object ({key: regex})! Good catch, and as always,
the one case that went untested. I'm preparing a fix now, thanks.


-- 
Zach Carter