ViewHelper index as JSON 

A manual that documents ViewHelpers with .. typo3:viewhelper:: is rendered with a viewhelpers.json beside its toc.json. It lists every ViewHelper by the name a template writes, with what the file describing it says and where the manual shows it:

{
  "project": {
    "title": "Fluid ViewHelper Reference",
    "version": "main",
    "permalink": "https://docs.typo3.org/permalink/t3viewhelper:{anchor}@main"
  },
  "viewhelpers": {
    "f:format.html": {
      "class": "TYPO3\\CMS\\Fluid\\ViewHelpers\\Format\\HtmlViewHelper",
      "namespace": "TYPO3\\CMS\\Fluid\\ViewHelpers",
      "xmlNamespace": "http://typo3.org/ns/TYPO3/CMS/Fluid/ViewHelpers",
      "summary": "ViewHelper to render a string which can contain HTML markup …",
      "documentation": "ViewHelper to render a string …",
      "docTags": {
        "@see": "https://docs.typo3.org/permalink/t3tsref:parsefunc"
      },
      "allowsArbitraryArguments": false,
      "source": "https://github.com/TYPO3/typo3/blob/main/…/Format/HtmlViewHelper.php",
      "arguments": {
        "current": {
          "type": "string",
          "required": false,
          "description": "Initialize the content object with this value …",
          "anchor": "viewhelper-argument-typo3-cms-fluid-viewhelpers-format-htmlviewhelper-current",
          "permalink": "https://docs.typo3.org/permalink/t3viewhelper:viewhelper-argument-…-current@main"
        }
      },
      "path": "Global/Format/Html",
      "anchor": "viewhelper-typo3-cms-fluid-viewhelpers-format-htmlviewhelper",
      "permalink": "https://docs.typo3.org/permalink/t3viewhelper:viewhelper-typo3-cms-fluid-viewhelpers-format-htmlviewhelper@main"
    }
  }
}

A ViewHelper is keyed by the prefix of its namespace, the namespaceAlias of the describing file, and its tag name: f:format.html, be:moduleLink, core:icon. That is the name a template uses and a reader looks for. objects.inv.json lists the same ViewHelpers by a key made from the class and a title without the prefix, and says nothing about them.

Each ViewHelper carries:

class, namespace, xmlNamespace

As the describing file states them.

summary

The first paragraph of the documentation, as plain text.

documentation

The documentation as the describing file writes it.

docTags

The doc tags of the class, such as @see or @deprecated. Left out where there are none.

allowsArbitraryArguments

Whether the ViewHelper takes arguments it does not declare.

source

The class on GitHub, where the describing file says where its sources are.

arguments

Each argument by its name, with its type, whether it is required, its default as a PHP literal where it has one, its description, and its own anchor and permalink.

path, anchor, permalink

The page that shows the ViewHelper, relative to this file and without an extension as in toc.json, its anchor, and the permalink built from it. A manual without an interlink shortcode has no permalinks.

A ViewHelper shown with :noindex: is listed where it is documented, not where it is shown again. A manual without ViewHelpers writes no viewhelpers.json.

For the Fluid ViewHelper Reference the file lists 159 ViewHelpers with 712 arguments in about 630 KB.