Re: Typed variadic template syntax?

[Ilya Yaroshenko]

On Thursday, 30 January 2014 at 15:28:34 UTC, Timon Gehr wrote:
On 01/30/2014 03:08 PM, Ilya Yaroshenko wrote:

2) `foreach` creates it's own scope. This won't work:
   foreach(i; TypeTuple!(1,2,3)){
       mixin("int num"~i.stringof~";");
   }
   num1=1;
   num2=2;
   num3=3;
   writeln(num1,num2,num3);

...
2) no. This should work for compile time foreach and 
TypeTuples. There
are many examples in source code of Phobos.

The following code fails to compile:

import std.typetuple, std.stdio;
void main(){
    foreach(i; TypeTuple!(1,2,3)){
        mixin("int num"~i.stringof~";");
    }
    num1=1;
    num2=2;
    num3=3;
    writeln(num1,num2,num3);
}

I am wrong, foreach always has own scope

    foreach(S; TypeTuple!(string, wstring, dstring))
    {
        import std.conv : to;
        S a = " a     bcd   ef gh ";
        assert(equal(splitter(a), [to!S("a"), to!S("bcd"), 
to!S("ef"), to!S("gh")]));
        a = "";
        assert(splitter(a).empty);
    }


You can use mixin and format instead:

import std.typetuple, std.stdio;
void main(){
    mixin(format("%(int num%s; %);", [1,2,3])); //<----
    num1=1;
    num2=2;
    num3=3;
    writeln(num1,num2,num3);
}