Null argument and function resolution

[Andrea Fontana via Digitalmars-d-learn]

Check this example:
http://dpaste.dzfl.pl/53f85bae4382

Calling with null, both c-tor match.
Is there a way to solve this?

Something like:

this(in ubyte* data) if( ??? )
{

}


Andrea

Re: Null argument and function resolution

[Adam D. Ruppe via Digitalmars-d-learn]

Two options:

1) add an overload that takes typeof(null)

this(typeof(null)) { /* handles the null literal specially */ }

2) Cast null to a specific type when making it:

new YourClass(cast(ubyte*) null);

Re: Null argument and function resolution

[Andrea Fontana via Digitalmars-d-learn]

The first answer is the one I was looking for. Very useful.
You should add to next this week in d tips.

On Wednesday, 27 May 2015 at 14:09:48 UTC, Adam D. Ruppe wrote:

Two options:

1) add an overload that takes typeof(null)

this(typeof(null)) { /* handles the null literal specially */ }

2) Cast null to a specific type when making it:

new YourClass(cast(ubyte*) null);

Re: Null argument and function resolution

[ketmar via Digitalmars-d-learn]

On Wed, 27 May 2015 14:09:47 +, Adam D. Ruppe wrote:

 Two options:
 
 1) add an overload that takes typeof(null)
 
 this(typeof(null)) { /* handles the null literal specially */ }

you keep breaking my box of thinking. ;-) never thought about such 
declaration.

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Re: Null argument and function resolution

[Meta via Digitalmars-d-learn]

On Wednesday, 27 May 2015 at 19:38:16 UTC, ketmar wrote:

On Wed, 27 May 2015 14:09:47 +, Adam D. Ruppe wrote:


Two options:

1) add an overload that takes typeof(null)

this(typeof(null)) { /* handles the null literal specially */ }


you keep breaking my box of thinking. ;-) never thought about 
such

declaration.


Unfortunately, there is no equivalent way to disable assignment 
of [] at compile time.


struct ArrayWrapper(T)
{
T[] a;

this(T[] arr) { a = arr; }

//Doesn't work; Conflicts with this(T[] arr)
//@disable this(typeof(this)[]);

//Doesn't work; hijacked by this(T[] arr)
//@disable this(typeof([]));
}

Re: Null argument and function resolution

[Timon Gehr via Digitalmars-d-learn]

On 05/27/2015 10:09 PM, Meta wrote:

On Wednesday, 27 May 2015 at 19:38:16 UTC, ketmar wrote:

On Wed, 27 May 2015 14:09:47 +, Adam D. Ruppe wrote:


Two options:

1) add an overload that takes typeof(null)

this(typeof(null)) { /* handles the null literal specially */ }


you keep breaking my box of thinking. ;-) never thought about such
declaration.


Unfortunately, there is no equivalent way to disable assignment of [] at
compile time.

struct ArrayWrapper(T)
{
 T[] a;

 this(T[] arr) { a = arr; }

 //Doesn't work; Conflicts with this(T[] arr)
 //@disable this(typeof(this)[]);

 //Doesn't work; hijacked by this(T[] arr)
 //@disable this(typeof([]));
}


https://issues.dlang.org/show_bug.cgi?id=7007