Idiom #332 List of the keys of a map

Create the list k containing all the keys of the map m

import static java.util.List.copyOf;
import java.util.List;

List<K> k = copyOf(m.keySet());

import java.util.ArrayList;
import java.util.List;

List<K> k = new ArrayList<>(m.keySet());

final k = m.keys;

import "golang.org/x/exp/maps"

k := maps.Keys(m)

k := make([]K, 0, len(m))
for key := range m {
	k = append(k, key)
}

@k = keys %m;

k = m.keys()

k = [*m.keys()]

k = list(m.keys())

k = m.keys

use std::collections::HashMap;

m.keys().collect::<Vec<_>>()

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