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9.1.1 Command Tree Element Opening Functions ¶

User defined functions called when an @-command element is first encountered are registered with texinfo_register_command_opening:

Function: texinfo_register_command_opening ($command_name, \&handler) ¶

$command_name is an @-command name, with the leading @. \&handler is the user defined function reference.

The call of the user defined functions is:

Function Reference: $text command_open ($converter, $command_name, \%element) ¶

$converter is a converter object. $command_name is the @-command name without the @. \%element is the Texinfo element.

The $text returned is prepended to the formatting of the @-command.

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

Function: \&default_command_open = $converter->default_command_open ($command_name) ¶

$command_name is the @-command name without the @. Returns the default opening function reference for $command_name, or ‘undef’ if there is none.