Method add_valueless

option_parser/src/lib.rs:217–227

Registers a flag-style option that does not take a value. When this option appears in the input string (without `=`), it is marked as set. Use [`is_set`](Self::is_set) to query it.

(&mut self, option: &str)

    /// When this option appears in the input string (without `=`), it is
    /// marked as set. Use [`is_set`](Self::is_set) to query it.
    pub fn add_valueless(&mut self, option: &str) -> &mut Self {
        self.options.insert(
            option.to_owned(),
            OptionParserValue {
                value: None,
                requires_value: false,
            },
        );

        self
    }

    /// Registers multiple flag-style options that do not take a value.
    ///