Outputs the file extension of the filename indicated by parameter {{{1}}}. In the File: namespace, this parameter defaults to {{PAGENAME}}. In all other namespaces, the default output is an empty string. Any uppercase letters in the file extension are changed to lowercase.
Usage
Input
Output
Notes
{{file extension}}
(empty string output because current page is in the Template: namespace)
{{file extension|Makefile}}
(empty string output because specified filename has no extension)
{{file extension|I-35.svg}}
svg
Input filename is acceptable with or without File: namespace prefix.
