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Programming-Idioms

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Idiom #335 List to map

Create the map m containing all the elements e of the list a, using as key the field e.id.

m = {e.id:e for e in a}
final m = {
  for (final e in a) e.id: e,
};
m := make(map[K]V, len(a))
for _, e := range a {
	m[e.id] = e
}
m = a.group_by(&:id)
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programming-idioms.org 
m = {e.id:e for e in a}
final m = {
  for (final e in a) e.id: e,
};
m := make(map[K]V, len(a))
for _, e := range a {
	m[e.id] = e
}
m = a.group_by(&:id)