Negative numbers

[Y-Less]

In my pulll request ( #6 ), I added syntax highlighting for the - in negative numbers. These highlight correctly:

a = -5;
a = 10 - 5;
a = 10 - -5;
a = 10--5;
a = 10-5;

These don't:

a = 10 -5;
a = (10)-5;

The lookbehind doesn't go far enough backwards to determine that - is not subtract in all cases. I think the total list of preceding symbols for which this becomes negate is = + - * / % & | ~ ! : ? ^ # > < ( , ;. Note the only place I can see an expression legally following ; and starting with a negative number is in a for loop yoda conditional: for (new i = 0; -5 > i; --i) {}.