Create module-level function using mixin template?

[Andy Valencia via Digitalmars-d-learn]

I have a code pattern, and would like to generate rather than 
copy/paste.  It _seems_ like mixin templates apply, but I'm not 
having much luck.  I saw one comment that templates always expand 
in their own context, so perhaps they're not useful for 
generating a top-level function?

Andy
```d
bool bigtest(in string s) {
    return true;
}

bool test1(in char c) {
    return false;
}
bool test2(in char c) {
    return true;
}

mixin template MyFunc(alias fn) {
    bool fn(in string s) {
        if (!bigtest(s)) {
            return false;
        }
        foreach(c; s) {
            if (!fn(c)) {
                return false;
            }
        }
        return true;
    }
}

mixin MyFunc!test1;
mixin MyFunc!test2;

int main() {
    if (!test1("Hello, world")) {
        return(1);
    }
    if (!test2("Hello, world")) {
        return(1);
    }
    return(0);
}
```