prepend_page_menu

Description:

public int prepend_page_menu (Widget child, Widget? tab_label, Widget? menu_label)

Prepends a page to this, specifying the widget to use as the label in the popup menu.

this	a `GtkNotebook`
child	the `GtkWidget` to use as the contents of the page
tab_label	the `GtkWidget` to be used as the label for the page, or null to use the default label, “page N”
menu_label	the widget to use as a label for the page-switch menu, if that is enabled. If null, and `tab_label` is a `GtkLabel` or null, then the menu label will be a newly created label with the same text as `tab_label`; if `tab_label` is not a `GtkLabel`, `menu_label` must be specified if the page-switch menu is to be used.

the index (starting from 0) of the prepended page in the notebook, or -1 if function fails