Re: Possible to overload assignment of struct field ??

[james.p.leblanc via Digitalmars-d-learn]

On Tuesday, 24 August 2021 at 05:34:08 UTC, Ali Çehreli wrote:

On 8/23/21 10:25 PM, james.p.leblanc wrote:

So, you need a "property". Easy... :)

1) Rename the member e.g. as a_.

2) Write setter and getter functions named 'a'.

struct Foo{
  int a_;

  int a() const {
return a_;
  }

  void a(int value) {
a_ = value;
  }
}

void main(){
  auto x = Foo(1);
  x.a = 100;
  assert(x.a == 100);
}

Ali


Ali,

Thank you ... yes!  This is exactly what I needed, I have done 
something
similar as you have shown for the "getter", but had a 
"brain-lock-up"

when thinking about the setter.

A bit embarassing for my, I admit.  But, on the positive side ... 
the

solution is now burned into my brain.

Thanks again and Kind Regards,
James

Re: Possible to overload assignment of struct field ??

[Ali Çehreli via Digitalmars-d-learn]

On 8/23/21 10:25 PM, james.p.leblanc wrote:

So, you need a "property". Easy... :)

1) Rename the member e.g. as a_.

2) Write setter and getter functions named 'a'.

struct Foo{
  int a_;

  int a() const {
return a_;
  }

  void a(int value) {
a_ = value;
  }
}

void main(){
  auto x = Foo(1);
  x.a = 100;
  assert(x.a == 100);
}

Ali

Possible to overload assignment of struct field ??

[james.p.leblanc via Digitalmars-d-learn]

Greetings,

With a struct, there are many overload possibilities available.

However, I haven't been able to find how to overload assignment
of **selected fields** of a struct.

For example, suppose:

struct Foo{
  int a;
  int b;
  ...
}

void main(){
auto x = Foo( 1, 2);  // so x now instantiates

x.a = 100; // suppose I wish to enforce that 
a<5??

...
}


(I understand this is basically a field "setter" idea that is most
often associated with classes.  So, another way to state the 
quesion
might be:  "How can a field setter be done on a **already 
instantiated**

struct?)

Best Regards,
James