Question

How do I figure out if an array contains an element? I thought there might be something like [1, 2, 3].includes(1) which would evaluate as true.

Was it helpful?

Solution

.contains() is the best method for lists, but for maps you will need to use .containsKey() or .containsValue()

[a:1,b:2,c:3].containsValue(3)
[a:1,b:2,c:3].containsKey('a')

OTHER TIPS

Some syntax sugar

1 in [1,2,3]

For lists, use contains:

[1,2,3].contains(1) == true

If you really want your includes method on an ArrayList, just add it:

ArrayList.metaClass.includes = { i -> i in delegate }

IMPORTANT Gotcha for using .contains() on a Collection of Objects, such as Domains. If the Domain declaration contains a EqualsAndHashCode, or some other equals() implementation to determine if those Ojbects are equal, and you've set it like this...

import groovy.transform.EqualsAndHashCode
@EqualsAndHashCode(includes = "settingNameId, value")

then the .contains(myObjectToCompareTo) will evaluate the data in myObjectToCompareTo with the data for each Object instance in the Collection. So, if your equals method isn't up to snuff, as mine was not, you might see unexpected results.

def fruitBag = ["orange","banana","coconut"]
def fruit = fruitBag.collect{item -> item.contains('n')}

I did it like this so it works if someone is looking for it.

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