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digitalmars.D - assign value to *this like in c++?

reply lyan <nothanks 0.0> writes:
Hi!

I just started with D, read already a bit through the 
documentation but I'm currently stuck here at porting my vector3 
class to D:

inline void normalize() {
   *this /= length();
}

How can I achieve that in D? Also: is there a way to overload /=, 
*/ operators?

Thanks for the help!
Jun 20 2019
next sibling parent reply lyan <nothanks 0.0> writes:
On Thursday, 20 June 2019 at 11:28:53 UTC, lyan wrote:

 Hi!

 I just started with D, read already a bit through the 
 documentation but I'm currently stuck here at porting my 
 vector3 class to D:

 inline void normalize() {
   *this /= length();
 }

 How can I achieve that in D? Also: is there a way to overload 
 /=, */ operators?

 Thanks for the help!


The code is C++ btw. and I had a typo below, I meant /= and *= 
operators.
Jun 20 2019
next sibling parent Basile B. <b2.temp gmx.com> writes:
On Thursday, 20 June 2019 at 11:31:19 UTC, lyan wrote:

 On Thursday, 20 June 2019 at 11:28:53 UTC, lyan wrote:

 Hi!

 I just started with D, read already a bit through the 
 documentation but I'm currently stuck here at porting my 
 vector3 class to D:

 inline void normalize() {
   *this /= length();
 }

 How can I achieve that in D? Also: is there a way to overload 
 /=, */ operators?

 Thanks for the help!


 The code is C++ btw. and I had a typo below, I meant /= and *= 
 operators.


Use `void opOpAssign(string op, T)(auto ref T t);` model to 
overload "DivAssisng" and "MulAssign". The compiler will 
instantiate the function template with the right `op` and `T` 
info when used in the code. These template parameters can be 
tested in a `static if` expression. See 
http://ddili.org/ders/d.en/operator_overloading.html for learning 
D operator overloads.

Note that these kind of questions should go in .learn : 
https://forum.dlang.org/group/learn
Jun 20 2019
prev sibling parent Nicholas Wilson <iamthewilsonator hotmail.com> writes:
On Thursday, 20 June 2019 at 11:31:19 UTC, lyan wrote:

 On Thursday, 20 June 2019 at 11:28:53 UTC, lyan wrote:

 Hi!

 I just started with D, read already a bit through the 
 documentation but I'm currently stuck here at porting my 
 vector3 class to D:

 inline void normalize() {
   *this /= length();
 }

 How can I achieve that in D? Also: is there a way to overload 
 /=, */ operators?

 Thanks for the help!


 The code is C++ btw. and I had a typo below, I meant /= and *= 
 operators.


If you're doing the porting to learn then what the others have 
said will get you there.

If you wan't to just get started with some 3d math there is 
https://github.com/d-gamedev-team/gfm (under math/gfm/math). Also 
useful to see what tricks they do to implement the features.

It you're new I can't recommend 
http://ddili.org/ders/d.en/index.html enough.

In future please post such questions to the learn forum.
Jun 20 2019
prev sibling next sibling parent XavierAP <n3minis-git yahoo.es> writes:
On Thursday, 20 June 2019 at 11:28:53 UTC, lyan wrote:

 Hi!

 I just started with D, read already a bit through the 
 documentation but I'm currently stuck here at porting my 
 vector3 class to D:

 inline void normalize() {
   *this /= length();
 }

 How can I achieve that in D? Also: is there a way to overload 
 /=, */ operators?

 Thanks for the help!


In C++ "this" is a pointer, but in D it's a reference -- so this 
should work:

this /= length();

BTW the empty () in function calls is optional in D; and see also 
"UFCS", which Bjarne S. wanted to get into C++ but ISO rejected 
it.

Yes it's possible to overload operators:

https://dlang.org/spec/operatoroverloading.html#op-assign

Note that these reserved functions to overload operators are 
templates. Therefore it's possible to generate code for several 
operators (e.g. + and - or more) with a single template and 
mixins; as shown in the examples in the link above.
Jun 20 2019
prev sibling parent lyan <nothanks 0.0> writes:
Thanks, those are very useful links.

 nogc Vector opUnary(string op)() pure const nothrow
   if (op == "+" || op == "-" || op == "~" || op == "!")
{
    Vector res = void;
    mixin(generateLoopCode!("res.v[ ] = " ~ op ~ " v[ ];", N)());
    return res;
}

wow...
Jun 20 2019