Programming-Idioms

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Idiom #52 Check if map contains value

Determine whether map m contains an entry with value v, for some key.

Illustration 
print "Found it!" if exists $m{$v};
#include <algorithm>
std::find_if(m.begin(), m.end(), [v](const auto& mo) {return mo.second == v; }) != m.end();
using System.Collections.Generic;
m.ContainsValue(v)
import std.algorithm;
m.byValue.canFind(v);
m.containsValue(v);
Map.values(m) |> Enum.member?(v)
func containsValue(m map[K]T, v T) bool {
	for _, x := range m {
		if x == v {
			return true
		}
	}
	return false
}
elem v (elems m)

Object.values(m).includes(v)
[...m.values()].includes(v)
import java.util.Map;
m.containsValue(v)
in_array($v, $m, true);
uses fgl;
m.IndexOfData(v) >= 0
v in m.values()
m.value?(v)
use std::collections::BTreeMap;
let does_contain = m.values()
        .any(|&val| *val == v);
!m.values.find(_ == v).isEmpty()
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Idiom created by

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Related idioms

print "Found it!" if exists $m{$v};
std::find_if(m.begin(), m.end(), [v](const auto& mo) {return mo.second == v; }) != m.end();
m.ContainsValue(v)
m.byValue.canFind(v);
m.containsValue(v);
Map.values(m) |> Enum.member?(v)
func containsValue(m map[K]T, v T) bool {
	for _, x := range m {
		if x == v {
			return true
		}
	}
	return false
}
elem v (elems m)

Object.values(m).includes(v)
[...m.values()].includes(v)
m.containsValue(v)
in_array($v, $m, true);
m.IndexOfData(v) >= 0
v in m.values()
m.value?(v)
let does_contain = m.values()
        .any(|&val| *val == v);
!m.values.find(_ == v).isEmpty()