le:
mbfl_declare_option BETA 123 b beta witharg "select beta value"
this code declares an option with arg... ch will be set to 123 by default and to the value selected on the command line if the option is used;
brief flag -b;
long flag --beta;
description select beta value, to be shown in the usage output.
If ... e variable script_option_BETA has been set to the selected value. Valid option usages are:
$ script.sh