rename renames the filenames supplied according to the rule specified as the first argument. The perlexpr argument is a Perl expression which is expected to modify the $_ string in Perl for at least some of the filenames specified. If a given filename is not modified by the expression, it will not be renamed. If no filenames are given on the command line, filenames will be read via standard input.
For example, to rename all files matching *.bak to strip the extension, you might say
To translate uppercase names to lower, you'd use
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