Help Parser IX: Revelations

#!/usr/bin/env ruby
require 'help_parser'

VERSION = '1.2.3'
OPTIONS = HelpParser[VERSION, <<-HELP]
# <= Hash here, parser skips
# HelpParser command example #

One can write any notes on the help text as long as
it does not start with a space or a "Keyword:".

Usage:
  revelations :options+ [<arg>]
  revelations :alternate <args=FLOAT>+
  revelations literal <arg1=WORD> <arg2=WORD>
  revelations <numbers=CSVI>+

The ":keyword" refers to a flag in defined in the "Keyword:" section.
A "[...]" is an optional part of the usage.
A "+" means one or more of it is allowed.

Options:
  -v --version \t Give version and quit
  -h --help    \t Give help and quit
  --verbose    \t Set $VERBOSE true
  --debug      \t Set $DEBUG true

The above(version, help, verbose, debug) are built-in options.
The tab, "\t", splits the comment from the flags.
On its own a flag is set to true, else it's nil.
But you can also set a long flag value to a string as allowed by its type.

  -a --all=YN y    \t Short, long, typed, and defaulted

OPTIONS.all at first is nil. If set without a value, it's set to "y"
One can set it to to either "n" of "y" as allowed by YN(see below under Types:).

  --stop=NUMBER    \t Typed
  --start=NUMBER 0 \t Typed and defaulted

  --rain
  --water
  --wet

  --to_be
  --not_to_be

Exclusive:
  to_be not_to_be \t Tells parser these are mutually exclusive keys
Inclusive:
  start stop      \t Tells parser any of these must include all of these
Conditional:
  rain water wet  \t Tells parser if first then all
                  \t Note how one can continue the comment as needed

Alternate:
  --sum
  --multiply

Types:
  WORD    /^[A-Za-z]+$/
  NUMBER  /^\\d+$/
  FLOAT   /^\\d+\\.\\d+$/
  YN      /^[YNyn]$/
  CSVI    /^\\d+(,\\d+)*$/
# <= Hash here, parser breaks out
And now one can freely write whatever....
HELP

# Tell HelpParser how to remap the string values:
HelpParser.integer(:stop, :start) # HelpParser.map(:stop, :start, map: :to_i)
HelpParser.float(:args)           # HelpParser.map(:args, map: :to_f)
# Also available: HelpParser.rational(*name) = HelpParser.map(*names, map: to_r)

# Tell HelpParser how to split the string values:
HelpParser.split(:numbers, sep: ',', map: :to_i)
# Also available: HelpParser.csv(*name) = HelpParser.split(*names)

# If one runs `revelations 1,2,3 4,5,6`, then:
OPTIONS.numbers #=> [[1, 2, 3], [4, 5, 6]]
# And everything else is unset:
OPTIONS.stop #=> nil