Options - self documenting go-lang command line parsing

The list of options a program wishes to use is specified as a lengthy, multi-line string. This string also serves as the help-string for the options.

Here is an example option specification:

Usage: example-tool
A short description of the command
--
flag        --flag,-f,FLAG           A description for this flag
option=     --option=,-o=,OPTION=    A description for this option
                                     the description continues here
!required=  --required,-r=,REQUIRED= A required option
--
env_var=    ENV_VAR=                 An environment variable
--
help        help,h                   Show this help message
run         run                      Run some function
--
Additional help for options or defaults etc. go here.

Read the documentation

Notes

Forked and modified from github.com/fd/options. I've retained the original license. Sadly, I didn't do a proper fork; so, my list of changes list is lost.

The godoc is here.