Merge commit '35dec7c96f7ee3eb17dd444f7067f0c776fb56ae'

docs/content/en/troubleshooting/inspection.md

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+---
+title: Data inspection
+linkTitle: Inspection
+description: Use template functions to inspect values and data structures.
+categories: [troubleshooting]
+keywords: []
+menu:
+  docs:
+    parent: troubleshooting
+    weight: 40
+weight: 40
+---
+
+Use the [`jsonify`] function to inspect a data structure:
+
+```go-html-template
+<pre>{{ jsonify (dict "indent" "  ") .Params }}</pre>
+```
+
+```text
+{
+  "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:
+
+```go-html-template
+<pre>{{ debug.Dump .Params }}</pre>
+```
+
+```text
+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.
+
+```go-html-template
+{{ $value := 42 }}
+{{ printf "%[1]v (%[1]T)" $value }} → 42 (int)
+```
+
+[`jsonify`]: /functions/encoding/jsonify
+[`debug.Dump`]: /functions/debug/dump
+[`printf`]: /functions/fmt/printf
+[`warnf`]: /functions/fmt/warnf