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Untitled.kt

How to get this right? Trying to check if some key,value pair is in a map

`in` is the representation for the `contains(...)` operator function <https://kotlinlang.org/docs/operator-overloading.html#in-operator>

So in IntelliJ you can always use `m.contains(...)` to see the auto complete suggestions, and there's none for checking if a Pair exists in a map.

~You can write your own one though:~

```@Deprecated("Bugged! See thread below")
operator fun <K, V> Map<K, V>.contains(keyValue: Pair<K, V>): Boolean =
  containsKey(keyValue.first) && containsValue(keyValue.second)```

or just write
```m["foo"] == 1
```
like a normal Map usage

<@U01681FLZC2> is there one for m.entries.contains()?

i am surprised if there is not anything built in for such a reasonable operation

<@U01681FLZC2> containsKey+containsValue doesn't mean it's in the same mapping…

<@UJQB4DJF7> your snippet assumes that "foo" is in the map

in kotlin you can do if m["key that has not been added yet"] == whatever

i mean that crashes in js, python i think too

&gt; containsKey+containsValue doesn't mean it's in the same mapping…
d'oh, true!

so it will just return undefined == 1 then?

but you wouldn't write that in Python either

for my use case I dont really want to use a map. I rather just want a set of pairs.

that should be easy with `in` keyword yeah?

what about instead of a map, use a list?

```    val m = listOf("foo" to 1, "bar" to 2)```