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12.2.2 Type Tree Element Opening Functions ¶

User defined functions called when an element without @-command with a container type is first encountered are registered with texinfo_register_type_opening:

Function: texinfo_register_type_opening ($type, \&handler) ¶

$type is the element type. \&handler is the user defined function reference.

The call of the user defined functions is:

Function Reference: $text type_open ($converter, $type, \%element) ¶

$converter is a converter object. $type is the element type. \%element is the Texinfo element.

The $text returned is prepended to the formatting of the type container.

It is possible to have access to the default opening function reference. The function used is:

Function: \&default_type_open = $converter->default_type_open ($type) ¶

$command_name is the element type. Returns the default opening function reference for $type, or ‘undef’ if there is none.

In the default conversion functions, this function is not often used, conversion is in general done after the elements inside of the type container have been formatted. This function is defined for inline text container elements to get text to prepend to their content (see Inline Text Containers Paragraph and Preformatted Formatting).