What does that even mean?

Scenario:

bool func(const ImVec2 label_size)
{
    return true;
}

void main()
{
    //first attempt:
    const ImVec2 label_size = CalcTextSize(label.ptr, null, true);
    //Error: cannot implicitly convert expression (CalcTextSize(cast(immutable(char)*)label, null, true, -1F)) of type ImVec2 to const(ImVec2)

    //second attempt
    const ImVec2 label_size = cast(const)CalcTextSize(label.ptr, null, true);
    // Error: cannot implicitly convert expression (CalcTextSize(cast(immutable(char)*)label, null, true, -1F)) of type const(ImVec2) to const(ImVec2)

    //third attempt
    const auto label_size = CalcTextSize(label.ptr, null, true);
    //Okay: don't know why the other two didn't work but I can keep going for now

    func(label_size);
    //Error: function imgui_d.func (const(ImVec2) label_size) is not callable using argument types (const(ImVec2))
}

Sorry, rough day. Could someone please explain what this means and how do go about resolving it?

Thanks,
Andrew

It seems there are two different ImVec2 types. So ImVec2 is not same as ImVec2 :)

On Tue, May 30, 2017 at 12:09 PM, Andrew Edwards via Digitalmars-d-learn < digitalmars-d-learn@puremagic.com> wrote:

> What does that even mean?
>
> Scenario:
>
> bool func(const ImVec2 label_size)
> {
>     return true;
> }
>
> void main()
> {
>     //first attempt:
>     const ImVec2 label_size = CalcTextSize(label.ptr, null, true);
>     //Error: cannot implicitly convert expression
> (CalcTextSize(cast(immutable(char)*)label, null, true, -1F)) of type
> ImVec2 to const(ImVec2)
>
>     //second attempt
>     const ImVec2 label_size = cast(const)CalcTextSize(label.ptr, null,
> true);
>     // Error: cannot implicitly convert expression
> (CalcTextSize(cast(immutable(char)*)label, null, true, -1F)) of type
> const(ImVec2) to const(ImVec2)
>
>     //third attempt
>     const auto label_size = CalcTextSize(label.ptr, null, true);
>     //Okay: don't know why the other two didn't work but I can keep going
> for now
>
>     func(label_size);
>     //Error: function imgui_d.func (const(ImVec2) label_size) is not
> callable using argument types (const(ImVec2))
> }
>

On Tuesday, 30 May 2017 at 10:09:50 UTC, Andrew Edwards wrote:
> What does that even mean?
>
> Scenario:
>
> bool func(const ImVec2 label_size)
> {
>     return true;
> }
>
> void main()
> {
>     //first attempt:
>     const ImVec2 label_size = CalcTextSize(label.ptr, null, true);
>     //Error: cannot implicitly convert expression (CalcTextSize(cast(immutable(char)*)label, null, true, -1F)) of type ImVec2 to const(ImVec2)
>
>     //second attempt
>     const ImVec2 label_size = cast(const)CalcTextSize(label.ptr, null, true);
>     // Error: cannot implicitly convert expression (CalcTextSize(cast(immutable(char)*)label, null, true, -1F)) of type const(ImVec2) to const(ImVec2)
>
>     //third attempt
>     const auto label_size = CalcTextSize(label.ptr, null, true);
>     //Okay: don't know why the other two didn't work but I can keep going for now
>
>     func(label_size);
>     //Error: function imgui_d.func (const(ImVec2) label_size) is not callable using argument types (const(ImVec2))
> }

My immediate thought is 'is that the same ImVec2?' Do you have two definitions of ImVec2 laying about?

What's the output of this code, if you insert it somewhere in the above?

import std.traits;

pragma(msg, fqn!ImVec2);
pragma(msg, fqn!(typeof(CalcTextSize(label.ptr, null,
> true))));

--
  Biotronic

import std.traits : fqn = fullyQualifiedName;

On Tue, May 30, 2017 at 12:24 PM, Biotronic via Digitalmars-d-learn < digitalmars-d-learn@puremagic.com> wrote:

> On Tuesday, 30 May 2017 at 10:09:50 UTC, Andrew Edwards wrote:
>
>> What does that even mean?
>>
>> Scenario:
>>
>> bool func(const ImVec2 label_size)
>> {
>>     return true;
>> }
>>
>> void main()
>> {
>>     //first attempt:
>>     const ImVec2 label_size = CalcTextSize(label.ptr, null, true);
>>     //Error: cannot implicitly convert expression
>> (CalcTextSize(cast(immutable(char)*)label, null, true, -1F)) of type
>> ImVec2 to const(ImVec2)
>>
>>     //second attempt
>>     const ImVec2 label_size = cast(const)CalcTextSize(label.ptr, null,
>> true);
>>     // Error: cannot implicitly convert expression
>> (CalcTextSize(cast(immutable(char)*)label, null, true, -1F)) of type
>> const(ImVec2) to const(ImVec2)
>>
>>     //third attempt
>>     const auto label_size = CalcTextSize(label.ptr, null, true);
>>     //Okay: don't know why the other two didn't work but I can keep going
>> for now
>>
>>     func(label_size);
>>     //Error: function imgui_d.func (const(ImVec2) label_size) is not
>> callable using argument types (const(ImVec2))
>> }
>>
>
> My immediate thought is 'is that the same ImVec2?' Do you have two definitions of ImVec2 laying about?
>
> What's the output of this code, if you insert it somewhere in the above?
>
> import std.traits;
>
> pragma(msg, fqn!ImVec2);
> pragma(msg, fqn!(typeof(CalcTextSize(label.ptr, null,
>
>> true))));
>>
>
> --
>   Biotronic
>

On Tuesday, 30 May 2017 at 10:20:53 UTC, Andrew Edwards wrote:
> Sorry, rough day. Could someone please explain what this means and how do go about resolving it?
>
> Thanks,
> Andrew

If you want to resolve it just do

    const label_size = CalcTextSize(...);

but as others have mentioned make sure it is the right type (although if they are functionally identical it won't matter).

On Tuesday, 30 May 2017 at 10:31:24 UTC, Daniel Kozak wrote:
> import std.traits : fqn = fullyQualifiedName;

Darnit. I just googled the template and got a result talking about fqn!T. So yeah - this code:

import std.traits;

pragma(msg, fullyQualifiedName!ImVec2);
pragma(msg, fullyQualifiedName!(typeof(CalcTextSize(label.ptr, null, true))));

--
  Biotronic

On Tuesday, 30 May 2017 at 10:37:58 UTC, Biotronic wrote:
> On Tuesday, 30 May 2017 at 10:31:24 UTC, Daniel Kozak wrote:
>> import std.traits : fqn = fullyQualifiedName;
>
> Darnit. I just googled the template and got a result talking about fqn!T. So yeah - this code:
>
> import std.traits;
>
> pragma(msg, fullyQualifiedName!ImVec2);
> pragma(msg, fullyQualifiedName!(typeof(CalcTextSize(label.ptr, null, true))));
>
> --
>   Biotronic

This is exactly the cause. Output is follows:

    internal.ImVec2
    types.ImVec2

I'm leveraging types as I try to do my own port of the lib so CalcTextSize is returning an instance of ImVec2 as defined types and I'm trying to assign to one I have declared in internal.

Thanks.

On Tuesday, 30 May 2017 at 10:46:12 UTC, Andrew Edwards wrote:
> On Tuesday, 30 May 2017 at 10:37:58 UTC, Biotronic wrote:
>> On Tuesday, 30 May 2017 at 10:31:24 UTC, Daniel Kozak wrote:
>>> import std.traits : fqn = fullyQualifiedName;
>>
>> Darnit. I just googled the template and got a result talking about fqn!T. So yeah - this code:
>>
>> import std.traits;
>>
>> pragma(msg, fullyQualifiedName!ImVec2);
>> pragma(msg, fullyQualifiedName!(typeof(CalcTextSize(label.ptr, null, true))));
>>
>> --
>>   Biotronic
>
> This is exactly the cause. Output is follows:
>
>     internal.ImVec2
>     types.ImVec2
>
> I'm leveraging types as I try to do my own port of the lib so CalcTextSize is returning an instance of ImVec2 as defined types and I'm trying to assign to one I have declared in internal.
>
> Thanks.

Pleasure. :)

I don't know why you have two different ImVec2s, but you may have good reasons to. If they need to be separate, you'll need to write a conversion function between the two for the cases where you have one and want the other. This could be the constructor or opAssign, or a standalone function if you want to be more explicit about it.

I'd argue that error message could be improved upon, btw.

--
  Simen

http://forum.dlang.org/post/xpmpakmusudanwuzzezl@forum.dlang.org https://issues.dlang.org/show_bug.cgi?id=9631

On Tue, May 30, 2017 at 1:07 PM, Biotronic via Digitalmars-d-learn < digitalmars-d-learn@puremagic.com> wrote:

> On Tuesday, 30 May 2017 at 10:46:12 UTC, Andrew Edwards wrote:
>
>> On Tuesday, 30 May 2017 at 10:37:58 UTC, Biotronic wrote:
>>
>>> On Tuesday, 30 May 2017 at 10:31:24 UTC, Daniel Kozak wrote:
>>>
>>>> import std.traits : fqn = fullyQualifiedName;
>>>>
>>>
>>> Darnit. I just googled the template and got a result talking about fqn!T. So yeah - this code:
>>>
>>> import std.traits;
>>>
>>> pragma(msg, fullyQualifiedName!ImVec2);
>>> pragma(msg, fullyQualifiedName!(typeof(CalcTextSize(label.ptr, null,
>>> true))));
>>>
>>> --
>>>   Biotronic
>>>
>>
>> This is exactly the cause. Output is follows:
>>
>>     internal.ImVec2
>>     types.ImVec2
>>
>> I'm leveraging types as I try to do my own port of the lib so CalcTextSize is returning an instance of ImVec2 as defined types and I'm trying to assign to one I have declared in internal.
>>
>> Thanks.
>>
>
> Pleasure. :)
>
> I don't know why you have two different ImVec2s, but you may have good reasons to. If they need to be separate, you'll need to write a conversion function between the two for the cases where you have one and want the other. This could be the constructor or opAssign, or a standalone function if you want to be more explicit about it.
>
> I'd argue that error message could be improved upon, btw.
>
> --
>   Simen
>