Editing Array slicing (section)

===1999: [[D programming language|D]]===
Consider the array:

<syntaxhighlight lang="d">
int[] a = [2, 5, 7, 3, 8, 6, 4, 1];
</syntaxhighlight>

Take a slice out of it:

<syntaxhighlight lang="d">
int[] b = a[2 .. 5];
</syntaxhighlight>

and the contents of <code>b</code> will be <code>[7, 3, 8]</code>. The first index of the slice is inclusive, the second is exclusive.

<syntaxhighlight lang="d">
auto c = a[$ - 4 .. $ - 2];
</syntaxhighlight>

means that the dynamic array <code>c</code> now contains <code>[8, 6]</code> because inside the [] the <code>$</code> symbol refers to the length of the array.

D array slices are aliased to the original array, so:

<syntaxhighlight lang="d">
b[2] = 10;
</syntaxhighlight>

means that <code>a</code> now has the contents <code>[2, 5, 7, 3, 10, 6, 4, 1]</code>. To create a copy of the array data, instead of only an alias, do:

<syntaxhighlight lang="d">
auto b = a[2 .. 5].dup;
</syntaxhighlight>

Unlike Python, D slice bounds don't saturate, so code equivalent to this Python code is an error in D:

<syntaxhighlight lang="pycon">
>>> d = [10, 20, 30]
>>> d[1 : 5]
[20, 30]
</syntaxhighlight>