At the moment, if I download a compressed file, it could be any of a .tar.gz archive, a tar.bz2 arhive, a .zip archive or a .gz archive. And each time I do so, I have to remember what the command line options for that program are.Is there any CLI program where I can just go:undocompression somefile.??and let it figure out what format the archive is in? (overly long name used to avoid conflicting with any real program)
Is there any program to provide a consistent interface across multiple archive types?
command line;archive;compression
You can use p7zip. It automatically identifies the archive type and decompress it.p7zip is the command line version of  7-Zip for Unix/Linux, made by an  independent developer.7z e <file_name>