Getopt::tabular is a perl 5 module for table-driven argument parsing, vaguely inspired by john ousterhout's tk_parseargv.

some nice features of getopt::tabular are:
* command-line arguments are carefully type-checked, both by pattern and
number -- e.g. if an option requires two integers, getoptions makes sure
that exactly two integers follow it!
* the valid command-line arguments are specified in a data structure
separate from the call to getoptions; this makes it easier to have very
long lists of options, and to parse options from multiple sources
(e.g. the command line, an environment variable, and a configuration file).
* getopt::tabular can intelligently generate help text based on your option
descriptions.
* the type system is extensible, and if you can define your desired argument
type using a single perl regular expression then it's particularly easy to
extend.
* options can be abbreviated and come in any order.
* a "spoof" mode in which arguments are parsed without side-effects.