byPair

1 import std.algorithm.sorting : sort;
2 import std.typecons : tuple, Tuple;
3 
4 auto aa = ["a": 1, "b": 2, "c": 3];
5 Tuple!(string, int)[] pairs;
6 
7 // Iteration over key/value pairs.
8 foreach (pair; aa.byPair)
9 {
10     if (pair.key == "b")
11         pairs ~= tuple("B", pair.value);
12     else
13         pairs ~= pair;
14 }
15 
16 // Iteration order is implementation-dependent, so we should sort it to get
17 // a fixed order.
18 pairs.sort();
19 assert(pairs == [
20     tuple("B", 2),
21     tuple("a", 1),
22     tuple("c", 3)
23 ]);