Is there a way to get the names of the fields in a named tuple? It looks like the names are actually aliases.

Thanks,
JC

On 2013-03-25 23:58, Jonathan Crapuchettes wrote:
> Is there a way to get the names of the fields in a named tuple? It looks
> like the names are actually aliases.

Perhaps "fieldSpecs".

-- 
/Jacob Carlborg

On Tue, 26 Mar 2013 10:13:03 +0100, Jacob Carlborg wrote:

> On 2013-03-25 23:58, Jonathan Crapuchettes wrote:
>> Is there a way to get the names of the fields in a named tuple? It looks like the names are actually aliases.
> 
> Perhaps "fieldSpecs".

Well, that gets you a FieldSpec template which would work except that it is private. I can get around that using the .stringof and then parsing, but I wish there was a cleaner way to do it. If the FieldSpec template was moved into the public section, it would allow for the name member to be accessed.

On Tuesday, 26 March 2013 at 16:31:51 UTC, Jonathan Crapuchettes wrote:
> but I wish there was a cleaner way to do it. If the FieldSpec template
> was moved into the public section, it would allow for the name member to
> be accessed.


Not sure this qualifies as clean, but it's an option:

import std.typecons, std.stdio, std.traits, std.conv;

string[] tupleNames(T)()
{
    string[] names;
    uint count = 0;
    bool matchNext = false;
	foreach(m; __traits(allMembers,T))
	{
	    if (matchNext)
	    {
	        names ~= m;
	        matchNext = false;
	        count ++;
	    }

	    if (m == "_" ~ count.to!string)
            matchNext = true;
	}
	return names;

}

pragma(msg, tupleNames!(Tuple!(int,"a",float,"b",string,"c")));

void main(){ }