Re: How to cast arrays?
On Saturday, 2 March 2019 at 02:14:01 UTC, Murilo wrote:
How do I cast a ubyte[] into uint[]? It keeps raising an error,
I have read the documentation saying there are restrictions for
that concerning the length of the arrays.
By the way here is how:
void foo(){
ubyte[] x = [1,2];
auto y = (cast(int*) &x)[0..2];
writeln(y);
}
Matheus.
Re: How to cast arrays?
On Saturday, 2 March 2019 at 02:14:01 UTC, Murilo wrote: How do I cast a ubyte[] into uint[]? It keeps raising an error, I have read the documentation saying there are restrictions for that concerning the length of the arrays. https://dlang.org/spec/expression.html#cast_expressions "Casting a dynamic array to another dynamic array is done only if the array lengths multiplied by the element sizes match. The cast is done as a type paint, with the array length adjusted to match any change in element size. If there's not a match, a runtime error is generated." Matheus.
Re: How to cast arrays?
On Sat, Mar 02, 2019 at 02:14:01AM +, Murilo via Digitalmars-d-learn wrote: > How do I cast a ubyte[] into uint[]? It keeps raising an error, I have > read the documentation saying there are restrictions for that > concerning the length of the arrays. That depends on what you're trying to accomplish. Are you trying to *reinterpret* the ubytes as uints? I.e., every 4 ubytes will be interpreted as 1 uint? If so, cast(uint[]) is your ticket. And obviously it will require that the .length of the ubyte[] must be a multiple of uint.sizeof, since otherwise the last element would be malformed. And there will probably be alignment issues as well. However, if you're trying to *transcribe* ubyte values into uint, i.e., promote each ubyte value to uint, then what you want is NOT a cast, but a transcription, i.e., copy ubytes into uint with integer promotion. There are various ways of doing this; an obvious one is: ubyte[] bytes = ...; uint[] ints = bytes.map!(b => cast(uint) b).array; T -- Beware of bugs in the above code; I have only proved it correct, not tried it. -- Donald Knuth
How to cast arrays?
How do I cast a ubyte[] into uint[]? It keeps raising an error, I have read the documentation saying there are restrictions for that concerning the length of the arrays.
