hugo/docs/content/en/troubleshooting/inspection.md

title	linkTitle	description	categories	keywords	menu	weight
Data inspection	Inspection	Use template functions to inspect values and data structures.	troubleshooting		docs parent weight troubleshooting 40	40

Use the jsonify function to inspect a data structure:

<pre>{{ jsonify (dict "indent" "  ") .Params }}</pre>

{
  "date": "2023-11-10T15:10:42-08:00",
  "draft": false,
  "iscjklanguage": false,
  "lastmod": "2023-11-10T15:10:42-08:00",
  "publishdate": "2023-11-10T15:10:42-08:00",
  "tags": [
    "foo",
    "bar"
  ],
  "title": "My first post"
}

{{% note %}} Hugo will throw an error if you attempt to use the construct above to display context that includes a page collection. For example, in a home page template, this will fail:

{{ jsonify (dict "indent" " ") . }} {{% /note %}}

Use the debug.Dump function to inspect data types:

<pre>{{ debug.Dump .Params }}</pre>

maps.Params{
  "date": time.Time{},
  "draft": false,
  "iscjklanguage": false,
  "lastmod": time.Time{},
  "publishdate": time.Time{},
  "tags": []string{
    "foo",
    "bar",
  },
  "title": "My first post",
}

Use the printf function (render) or warnf function (log to console) to inspect simple data structures. The layout string below displays both value and data type.

{{ $value := 42 }}
{{ printf "%[1]v (%[1]T)" $value }} → 42 (int)