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Function `std.array.byPair`

Construct a range iterating over an associative array by key/value tuples.


						
				auto byPair(AA)
				(
				

				  AA aa
				

				)
				

				if (isAssociativeArray!AA);

Parameters

Name	Description
aa	The associative array to iterate over.

Returns

A forward range of Tuple's of key and value pairs from the given associative array. The members of each pair can be accessed by name (.key and .value). or by integer index (0 and 1 respectively).

Example

import std.algorithm.sorting : sort;
import std.typecons : tuple, Tuple;

auto aa = ["a": 1, "b": 2, "c": 3];
Tuple!(string, int)[] pairs;

// Iteration over key/value pairs.
foreach (pair; aa.byPair)
{
    if (pair.key == "b")
        pairs ~= tuple("B", pair.value);
    else
        pairs ~= pair;
}

// Iteration order is implementation-dependent, so we should sort it to get
// a fixed order.
pairs.sort();
assert(pairs == [
    tuple("B", 2),
    tuple("a", 1),
    tuple("c", 3)
]);

Authors

Andrei Alexandrescu and Jonathan M Davis

License

Boost License 1.0.