-```-t <val>```: Value type: string, number, boolean (default)
-```-m <val>```: Method: set (DEFAULT: simple value where $<variablename> will be a simple value), add (list with several values where $<variablename> will be a bash array)
-```-k <val>```: Custom check method (bash function like bashopts_check_number in bashopts.sh file)