On Saturday, 4 March 2017 at 17:11:46 UTC, Andrey wrote:
Hello, is there any way to using in expression like in python,
e.g.
if 4 in [1, 3, 4]:
do something
My code in D
if (regionAlign in [RegionAlign.top, RegionAlign.bottom]) {
...
}
throws an error:
incompatible types for (((cast(Widget)this).regionAlign()) in
([top, bottom])): 'RegionAlign' and 'RegionAlign[]'
The reason this is disallowed for normal arrays is that finding a
key in an array is O(n) while finding a key in an associative
array is O(1). Rather than let users unknowingly write code that
looks the same but is far slower for arrays, D doesn't allow
this. You can use std.algorithm.among, however.
import std.algorithm;
if (regionAlign.among!(RegionAlign.top, RegionAlign.bottom))
{
//etc.
}
http://dlang.org/phobos/std_algorithm_comparison.html#.among
