Determining if a class has a template function

[Meta via Digitalmars-d-learn]

On Wednesday, 12 October 2016 at 16:57:50 UTC, Meta wrote:
> //A template function's .stringof is of the format <function 
> name>(<template args>)(<function args>)
> //so match on the number of brackets to determine whether it's 
> a template function or not
> enum isTemplateFunction = __traits(isTemplate, f)
>                               && fstr.balancedParens('(', ')')
>                               && (fstr.canFind("if")
>                                   || fstr.count!(c =>
>                                          
> cast(bool)c.among!('(', ')')) == 4);

Whoops, I forget to say that fstr is defined like this:

enum fstr = f.stringof;