Filter an array so that duplicate items are removed
1-byte built-ins
05AB1E (legacy)
Ù

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Alternatively:
ê

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APL (Dyalog Unicode)
∪

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Jelly
Q

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W
U

Stax
u

MATL
u

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MathGolf
▀

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Seriously/Actually
╔

Japt
â

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Pyth
{

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Husk
u

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Pyke
}

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Canvas
Ｄ

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