Does D provide anything like this? Otherwise, was this ever
considered and were reasons found not to have it?
I mean at least in C# (not talking about C/C++ at all) you can
declare two kind of multi-dimensional arrays: T[][][] or T[,,].
The first is the same as the D ones, array of arrays of...
(except the order of the indices isn't inverted in C# type
declarations IIRC); but the second provides contiguous,
rectangular truly multi-dimensional arrays supposedly with one
single level of indirection. (Of course static arrays don't exist
in C# just dynamic but that's an apart issue.)
Is there a reason why this feature would not be really desirable
or possible? Does it really exist and I missed it in Andrei's
book? As a matter of fact he states in chapter 4.3:
«On the minus side, "tall and thin" arrays with many rows and few
columns incur a large size overhead as there's one array to keep
per column. [...] Jagged arrays may have problems with efciency
of access and cache friendliness. Each element access requires
two indirections [...] going column-wise through a jagged array
is a cache miss bonanza.»
It would look that well implemented [,,] arrays would fill some
application gaps, even though arrays of arrays (jagged in
practice or not) are elsewhere useful as well of course. In the
former cases I would think about defining my own struct wrapping
a flat array with an n-dimensional api such as return _buff[i*m +
j]... but generic in type and maybe also in dimension.
Again any special reason why this isn't already provided in the
language? Either a generic struct/class like that, or something
deeper in the language that allows using the [] operator as
transparently as with any other arrays (as in C#).
Thanks for any input.
- multi-dimensional arrays, not arra... XavierAP via Digitalmars-d-learn
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