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Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle)

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On 12/18/2019 10:34 PM, Mr Flibble wrote:
> Hi!
> 
> The following is the base class of my vector class (the mathematical 
> vector not the container) so I can do things like:
> 
> vec3 v1 = { 1.0, 2.0, 3.0 };
> vec2 v2 = v1.xy;
> double z = v1.z;
> vec4 v3 = v1.xyzz;
> 
> So we have an anonymous union of an anonymous struct and some swizzles 
> and I suspect it is full of UB but I am finding it hard to care as I 
> cannot see any other way of doing this.
> 
> Collective thoughts/wisdom?

Sounds like a union is not the right tool, unless I am misinterpreting 
the purpose.
Possibly xy, z, xyz etc. should be object members that overload the 
assignment and type cast (aka user-defined conversion) operators.
Inside the body of the overloads you perform the actions you need on the 
vector (so you need a reference to the vector inside the members).

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Probably UB but I am finding it hard to give a fuck (C++ swizzle) Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-12-18 21:34 +0000
  Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Öö Tiib <ootiib@hot.ee> - 2019-12-18 14:24 -0800
    Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-12-18 23:14 +0000
      Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Öö Tiib <ootiib@hot.ee> - 2019-12-18 15:36 -0800
        Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-12-19 06:18 +0000
      Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-12-19 10:49 +0100
      Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Manfred <noname@add.invalid> - 2019-12-19 14:29 +0100
  Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-12-18 15:38 -0800
    Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-12-19 06:19 +0000
      Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-12-23 10:34 -0800
      Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-12-28 00:30 -0800
        Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Mr Flibble <flibble@i42.removethisbit.co.uk> - 2019-12-28 15:53 +0000
          Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-31 23:00 -0800
  Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Manfred <noname@add.invalid> - 2019-12-19 14:25 +0100
  Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) woodbrian77@gmail.com - 2019-12-20 08:22 -0800
    Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-12-21 13:23 +0000
  Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-11 15:08 -0800
    Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Bonita Montero <Bonita.Montero@gmail.com> - 2020-02-10 18:35 +0100
      Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-02-10 14:07 -0800
  Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-31 21:42 -0800

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