Using commas in filenames feels kind of weird to me, but I do use a comma as the initiator for my Bash key sequences.
For example:
,, expands to $
,h expands to --help
,v expands to --version
,s prefixes sudo
You put keyseqs in ~/.inputc, set a keyseq-timeout, and it just works.
You put keyseqs in ~/.inputc, set a keyseq-timeout, and it just works.