collections.Union
Syntax
collections.Union SET1 SET2 ⟼ any
Alias
union
Given two arrays (or slices) A and B, this function will return a new array that contains the elements or objects that belong to either A or to B or to both. The elements supported are strings, integers, and floats (only float64).
{{ union (slice 1 2 3) (slice 3 4 5) }}
<!-- returns [1 2 3 4 5] -->
{{ union (slice 1 2 3) nil }}
<!-- returns [1 2 3] -->
{{ union nil (slice 1 2 3) }}
<!-- returns [1 2 3] -->
{{ union nil nil }}
<!-- returns an error because both arrays/slices have to be of the same type -->
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
.