Creating implementation for idiom 332 : List of the keys of a map

Idiom

# 332 List of the keys of a map

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

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final k = m.keys;

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

k := maps.Keys(m)

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

Demo

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

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

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

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

fgl

type
  TList = specialize TFPGList<TKey>;
  TMap = specialize TFPGMap<TKey, TData>;

var
  m: TMap;
  k: TList;

begin
  ....
  k := TList.Create;
  for idx := 0 to m.Count-1 do k.Add(m.Keys[idx]);
  .....
  k.Free;
  ....

@k = keys %m;

k = m.keys()

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k = [*m.keys()]

k = list(m.keys())

k = m.keys

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use std::collections::HashMap;

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

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