On Friday, 19 June 2015 at 14:42:59 UTC, Steven Schveighoffer
wrote:
On 6/19/15 10:13 AM, Quentin Ladeveze wrote:
On Friday, 19 June 2015 at 14:04:05 UTC, Daniel Kozák wrote:
On Fri, 19 Jun 2015 13:52:52 +0000
Quentin Ladeveze via Digitalmars-d-learn
<digitalmars-d-learn@puremagic.com> wrote:
On Friday, 19 June 2015 at 13:38:45 UTC, Steven
Schveighoffer wrote:
>
> Does this work for you, or is there a further expectation?
>
> auto asTuple() { return Tuple!(int, "a", ...)(a, b, >
> stringValue);}
>
> -Steve
In fact, I was trying to use traits to create the tuple
automatically and being able to add or remove methods to the
struct without breaking the asTuple method.
I used allMembers for the name of the methods, but I didn't
found
anything for their return types or their values.
Thank you.
http://dlang.org/phobos/std_traits.html#ReturnType
http://dlang.org/phobos/std_traits.html#ParameterTypeTuple
These are interesting and can be useful, but allMembers
returns strings
and not functions, so I can't apply ReturnType.
It's a *compile time* string. D is able to do some amazing
things with this :)
// assuming 'a' is the first member
mixin("alias aReturnType = ReturnType!(Example." ~
__traits(allMembers, Example)[0] ~ ");");
static assert(is(aReturnType == int));
Using foreach over allMembers, you can construct a perfect
return tuple using introspection and mixin.
-Steve
I would never have thought about mixins, this is amazing ! But
thinking at compile time still is a little difficult for me, and
now I don't understand how you can construct your tuple. I've
been trying to create a string, by iterating on allMembers and
concatenating the result of my functions in a string. But of
course, I cannot use this string at compile time.
Now I know there is a way t do it, but my brain just can't figure
it out.
Can you help me ?
