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digitalmars.D - Creation of an array which length depens on variables not possible?

reply TheDGuy <loder.feuer googlemail.com> writes:
Why is this not possible?

		GtkAllocation size;
		widget.getAllocation(size);
		this.width = size.width;
		this.height = size.height;

		int[size.width*size.height*3+1] arr;
		this.accumulator = arr;

nor this:

		GtkAllocation size;
		widget.getAllocation(size);
		this.width = size.width;
		this.height = size.height;

		int[this.width*this.height*3+1] arr;
		this.accumulator = arr;

in the constructor?
Dec 26 2015
parent reply Adam D. Ruppe <destructionator gmail.com> writes:
On Saturday, 26 December 2015 at 18:43:51 UTC, TheDGuy wrote:

 Why is this not possible?

 		int[size.width*size.height*3+1] arr;


Try:

auto arr = new int[](size.width*size.height*3+1);


The int[x] syntax declares a statically sized array - statically 
sized meaning it must be known at compile time and thus cannot be 
variables, along a few other differences.

The new array syntax though returns one of variable size.
Dec 26 2015
parent TheDGuy <loder.feuer googlemail.com> writes:
On Saturday, 26 December 2015 at 18:49:26 UTC, Adam D. Ruppe 
wrote:

 On Saturday, 26 December 2015 at 18:43:51 UTC, TheDGuy wrote:

 Why is this not possible?

 		int[size.width*size.height*3+1] arr;


 Try:

 auto arr = new int[](size.width*size.height*3+1);


 The int[x] syntax declares a statically sized array - 
 statically sized meaning it must be known at compile time and 
 thus cannot be variables, along a few other differences.

 The new array syntax though returns one of variable size.


Thank you very much, it really helped me a lot!
Dec 26 2015