hugo/docs/content/en/functions/collections/Union.md

title, description, categories, keywords, params, aliases

title	description	categories	keywords	params	aliases
collections.Union	Returns a slice containing the unique elements from two given slices.			functions_and_methods aliases returnType signatures union []any collections.Union SLICE1 SLICE2	/functions/union

{{ union (slice 1 2 3) (slice 3 4 5) }} → [1 2 3 4 5]
{{ union (slice 1 2 3) nil }}           → [1 2 3]
{{ union nil (slice 1 2 3) }}           → [1 2 3]
{{ union nil nil }}                     → []

OR filter in where query

This is also very useful to use as OR filters when combined with where:

{{ $pages := where .Site.RegularPages "Type" "not in" (slice "page" "about") }}
{{ $pages = $pages | union (where .Site.RegularPages "Params.pinned" true) }}
{{ $pages = $pages | intersect (where .Site.RegularPages "Params.images" "!=" nil) }}

The above fetches regular pages not of page or about type unless they are pinned. And finally, we exclude all pages with no images set in Page parameters.

See intersect for AND.