hugoDocs/content/functions/where.md

title	linktitle	description	godocref	date	publishdate	lastmod	categories	tags	signature	workson	hugoversion	relatedfuncs	deprecated	toc	needsexample
where	where	Filters an array to only the elements containing a matching value for a given field.		2017-02-01	2017-02-01	2017-02-01	functions	filtering		lists taxonomies terms groups		intersect first	false	true	true

where filters an array to only the elements containing a matching value for a given field.

{{ range where .Data.Pages "Section" "post" }}
  {{ .Content }}
{{ end }}

It can be used by dot-chaining the second argument to refer to a nested element of a value.

+++
series: golang
+++

{{ range where .Site.Pages "Params.series" "golang" }}
   {{ .Content }}
{{ end }}

It can also be used with the logical operators !=, >=, in, etc. Without an operator, where compares a given field with a matching value equivalent to =.

{{ range where .Data.Pages "Section" "!=" "post" }}
   {{ .Content }}
{{ end }}

The following logical operators are vailable with where:

• =, ==, eq: True if a given field value equals a matching value
• !=, <>, ne: True if a given field value doesn't equal a matching value
• >=, ge: True if a given field value is greater than or equal to a matching value
• >, gt: True if a given field value is greater than a matching value
• <=, le: True if a given field value is lesser than or equal to a matching value
• <, lt: True if a given field value is lesser than a matching value
• in: True if a given field value is included in a matching value. A matching value must be an array or a slice
• not in: True if a given field value isn't included in a matching value. A matching value must be an array or a slice
• intersect: True if a given field value that is a slice / array of strings or integers contains elements in common with the matching value. It follows the same rules as the intersect function.

Using where with intersect

{{ range where .Site.Pages ".Params.tags" "intersect" .Params.tags }}
  {{ if ne .Permalink $.Permalink }}
    {{ .Render "summary" }}
  {{ end }}
{{ end }}

Using where with first

{{ range first 5 (where .Data.Pages "Section" "post") }}
   {{ .Content }}
{{ end }}

Nesting where Clauses

Needs Example

Unset Fields

Filtering only works for set fields. To check whether a field is set or exists, you can use the operand nil.

This can be useful to filter a small amount of pages from a large pool. Instead of set field on all pages, you can set field on required pages only.

Only the following operators are available for nil

• =, ==, eq: True if the given field is not set.
• !=, <>, ne: True if the given field is set.

{{ range where .Data.Pages ".Params.specialpost" "!=" nil }}
   {{ .Content }}
{{ end }}