Struct Options

pub struct Options {
    pub(crate) grps: Vec<OptGroup>,
    pub(crate) parsing_style: ParsingStyle,
    pub(crate) long_only: bool,
}

A description of the options that a program can handle.

Fields

grps: Vec<OptGroup>

parsing_style: ParsingStyle

long_only: bool

Implementations

impl Options

pub fn new() -> Options

Create a blank set of options.

pub fn parsing_style(&mut self, style: ParsingStyle) -> &mut Options

Set the parsing style.

pub fn long_only(&mut self, long_only: bool) -> &mut Options

Set or clear “long options only” mode.

In “long options only” mode, short options cannot be clustered together, and long options can be given with either a single “-” or the customary “–”. This mode also changes the meaning of “-a=b”; in the ordinary mode this will parse a short option “-a” with argument “=b”; whereas in long-options-only mode the argument will be simply “b”.

pub fn opt( &mut self, short_name: &str, long_name: &str, desc: &str, hint: &str, hasarg: HasArg, occur: Occur, ) -> &mut Options

Create a generic option group, stating all parameters explicitly.

pub fn optflag( &mut self, short_name: &str, long_name: &str, desc: &str, ) -> &mut Options

Create a long option that is optional and does not take an argument.

• short_name - e.g. "h" for a -h option, or "" for none
• long_name - e.g. "help" for a --help option, or "" for none
• desc - Description for usage help

pub fn optflagmulti( &mut self, short_name: &str, long_name: &str, desc: &str, ) -> &mut Options

Create a long option that can occur more than once and does not take an argument.

• short_name - e.g. "h" for a -h option, or "" for none
• long_name - e.g. "help" for a --help option, or "" for none
• desc - Description for usage help

pub fn optflagopt( &mut self, short_name: &str, long_name: &str, desc: &str, hint: &str, ) -> &mut Options

Create a long option that is optional and takes an optional argument.

• short_name - e.g. "h" for a -h option, or "" for none
• long_name - e.g. "help" for a --help option, or "" for none
• desc - Description for usage help
• hint - Hint that is used in place of the argument in the usage help, e.g. "FILE" for a -o FILE option

pub fn optmulti( &mut self, short_name: &str, long_name: &str, desc: &str, hint: &str, ) -> &mut Options

Create a long option that is optional, takes an argument, and may occur multiple times.

• short_name - e.g. "h" for a -h option, or "" for none
• long_name - e.g. "help" for a --help option, or "" for none
• desc - Description for usage help
• hint - Hint that is used in place of the argument in the usage help, e.g. "FILE" for a -o FILE option

pub fn optopt( &mut self, short_name: &str, long_name: &str, desc: &str, hint: &str, ) -> &mut Options

Create a long option that is optional and takes an argument.

• short_name - e.g. "h" for a -h option, or "" for none
• long_name - e.g. "help" for a --help option, or "" for none
• desc - Description for usage help
• hint - Hint that is used in place of the argument in the usage help, e.g. "FILE" for a -o FILE option

pub fn reqopt( &mut self, short_name: &str, long_name: &str, desc: &str, hint: &str, ) -> &mut Options

Create a long option that is required and takes an argument.

• short_name - e.g. "h" for a -h option, or "" for none
• long_name - e.g. "help" for a --help option, or "" for none
• desc - Description for usage help
• hint - Hint that is used in place of the argument in the usage help, e.g. "FILE" for a -o FILE option

pub fn parse<C: IntoIterator>(&self, args: C) -> Result

where C::Item: AsRef<OsStr>,

Parse command line arguments according to the provided options.

On success returns Ok(Matches). Use methods such as opt_present opt_str, etc. to interrogate results.

Panics

Returns Err(Fail) on failure: use the Debug implementation of Fail to display information about it.

pub fn short_usage(&self, program_name: &str) -> String

Derive a short one-line usage summary from a set of long options.

pub fn usage(&self, brief: &str) -> String

Derive a formatted message from a set of options.

pub fn usage_with_format<F: FnMut(&mut dyn Iterator<Item = String>) -> String>( &self, formatter: F, ) -> String

Derive a custom formatted message from a set of options. The formatted options provided to a closure as an iterator.

pub(crate) fn usage_items<'a>(&'a self) -> Box<dyn Iterator<Item = String> + 'a>

Derive usage items from a set of options.

Trait Implementations

impl Default for Options

fn default() -> Self

Returns the “default value” for a type.