Finding all Functions in a Module

Level:	Novice
Cookbook Type:	Recipe
Cookbook Status:	Draft
Approximate reading time:	15 min 0.249 hr
D Version:	D2

This recipe shows how to list all functions in a module. More generally, it can be used to list all symbols in a module and filter them according to a specific predicate.

First, we need a tuple of all symbol names in a module:

__traits(allMembers, mymodule)

Note that __traits(allMembers, XXX) returns a tuple of strings, not a tuple of symbols.

To iterate on this tuple, a simple foreach works very well. On a tuple, foreach is unrolled at compile-time.

foreach(m; __traits(allMembers, mymodule)) 
{
   //
}

Inside the foreach loop, we can use __traits(getMember, parentSymbol, name) to transform name (a string) into a real symbol. Then static if will test each symbol in turn. Here the predicate is __traits(isStaticFunction, XXX):

Program Code

module mymodule;
import std.stdio : writeln;

void main() {

    foreach(m; __traits(allMembers, mymodule)) 
    {
        static if (__traits(isStaticFunction, __traits(getMember, mymodule, m))) 
            writeln(m);     
    }
}

void myfunc() {}

int myOtherFunc(int i) { return i+1; }

Compilation Output

main
myfunc
myOtherFunc