module mytuple;

import dranges.templates;
import dranges.typetuple;
import std.traits;
import std.conv;

template containsStrings( T... ) {
    enum containsStrings = StaticFilter!( isSomeString, StaticMap!( TypeOf, StaticFilter!( isAlias, T ) ) ).length != 0;
}

mixin template TupleNameAccess( int index, string name, T... ) {
    mixin( "ref auto " ~ name ~ "( ) { return t.field[" ~ to!string(index) ~ "]; }" );
    static if ( T.length > 0 ) {
        mixin TupleNameAccess!( index + 1, T );
    }
}

struct Tuple( T... ) if ( containsStrings!T ) {
    alias StaticFilter!( isType, T ) Types;
    alias StaticFilter!( isAlias, T ) Names;
    Tuple!Types t;
    alias t this;

    this( Types args ) {
        t = typeof( t )( args );
    }

    mixin TupleNameAccess!( 0, Names );
}

struct Tuple( T... ) if ( !containsStrings!T ) {
    T field;
    alias field expand;
    //alias field this;

    enum length = T.length;

    this( T args ) {
        field = args;
    }

    Tuple!( T, U ) opBinary( string op : "~", U... )( Tuple!U arg ) {
        return Tuple!( T, U )( expand, arg.expand );
    }
}

Tuple!T tuple( T... )( T args ) {
    return Tuple!T( args );
}

unittest {
    auto a = tuple( 1, 'a' );
    auto b = tuple( 1.2, "b" );
    auto c = a ~ b;
    assert( c == tuple( 1, 'a', 1.2, "b" ) );

    auto o = Tuple!( int, "a", string, "b" )( 1, "a" );
    auto n = Tuple!( int, "r", string, "g" )( 1, "a" );
    assert( o == n );
}

void main( ) {
}