define_option {defineOptions}

Function to define an option for argument parsing

Description

define_option function adds a new definition for argument parsing.

Usage

## S4 method for signature 'ParserDef,list'
define_option(obj,new_setting)

Arguments

obj

ParserDef S4 object

new_setting

list

Details

define_option is a S4 method of ParserDef class. This method adds a definition of argument parsing to a ParserDef object. new_setting argument requires a list that consists of def_name, def_type, long_option, short_option, input_splitter and callback. def_name, def_type, long_option or short_option and callback are required elements. def_name is an identifier of this definition and also works as a name of an element of a list as the final parsing result. def_type is a type to which each input value is cast into. long_option or short_option defines a part of command line options strting from dash such as "–output" and "-o". input_splitter splits input value with the characters specified. Callback is important and defines how the option should be specified. callbacks document describes its detail.

Value

ParserDef object

See Also

ParserDef-class defineOptions-package

Examples

parser_def = new_parser_def() |>
    define_option(
        list(
            def_name = "target_range",
            def_type = "integer",
            long_option = "--target-range",
            short_option = "-t",
            input_splitter = ",",
            callback = opt_optional_input_required( input_when_omitted = "70,180" )
        )
    ) |>
    define_option(
        list(
            def_name = "exclude_weekend",
            def_type = "logical",
            long_option = "--exclude-weekend",
            callback = opt_optional_input_disallowed( input_when_specified = "TRUE",
                                                      input_when_omitted = "FALSE" )
        )
    )|>
    define_option(
        list(
            def_name = "output_path",
            def_type = "character",
            long_option = "--output",
            callback = opt_required_input_required()
        )
    )