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Idiom #52 Check if map contains value

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

Is this value contained in this map, for any key? 
import std.algorithm;
m.byValue.canFind(v);
(boolean (some #{v} (vals m)))
#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)
m.containsValue(v);
Map.values(m) |> Enum.member?(v)
func containsValue[M ~map[K]V, K, V comparable](m M, v V) bool {
	for _, x := range m {
		if x == v {
			return true
		}
	}
	return false
}
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)
m.containsValue(v)
in_array($v, $m, true);
uses fgl;
m.IndexOfData(v) >= 0
print "Found it!" if exists $m{$v};
def k(x, m):
    for k, v in m.items():
        if v == x: return k
k = k(v, m) or False
x = False
for y in m.items():
    if y[1] == v:
        x = y[0]
        break
v in m.values()
m.value?(v)
use std::collections::BTreeMap;
let does_contain = m.values().any(|&val| *val == v);
m.valuesIterator.contains(v)
m includes: v.
New implementation...
< > ⌨
programming-idioms.org 
m.byValue.canFind(v);
(boolean (some #{v} (vals m)))
std::find_if(m.begin(), m.end(), [v](const auto& mo) {return mo.second == v; }) != m.end();
m.ContainsValue(v)
m.containsValue(v);
Map.values(m) |> Enum.member?(v)
func containsValue[M ~map[K]V, K, V comparable](m M, v V) bool {
	for _, x := range m {
		if x == v {
			return true
		}
	}
	return false
}
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)
m.containsValue(v)
in_array($v, $m, true);
m.IndexOfData(v) >= 0
print "Found it!" if exists $m{$v};
def k(x, m):
    for k, v in m.items():
        if v == x: return k
k = k(v, m) or False
x = False
for y in m.items():
    if y[1] == v:
        x = y[0]
        break
v in m.values()
m.value?(v)
let does_contain = m.values().any(|&val| *val == v);
m.valuesIterator.contains(v)
m includes: v.