Struct ParseArgument

pub struct ParseArgument<T> { /* private fields */ }

Parser for a named argument, created with argument.

Implementations

impl<T> ParseArgument<T>

pub fn help<M>(self, help: M) -> Self

where M: Into<Doc>,

Add a help message to an argument

See NamedArg::help

impl<T> ParseArgument<T>

pub fn adjacent(self) -> Self

Restrict parsed arguments to have both flag and a value in the same word:

In other words adjacent restricted ParseArgument would accept --flag=value or -fbar but not --flag value. Note, this is different from adjacent, just plays a similar role.

Should allow to parse some of the more unusual things

Combinatoric example

#[derive(Debug, Clone)]
pub struct Options {
    package: String,
}

fn package() -> impl Parser<String> {
    long("package")
        .short('p')
        .help("Package to use")
        .argument("SPEC")
        .adjacent()
}

pub fn options() -> OptionParser<Options> {
    construct!(Options { package() }).to_options()
}

fn main() {
    println!("{:?}", options().run())
}

Derive example

#[derive(Debug, Clone, Bpaf)]
#[bpaf(options)]
pub struct Options {
    #[bpaf(short, long, argument("SPEC"), adjacent)]
    /// Package to use
    package: String,
}

fn main() {
    println!("{:?}", options().run())
}

Output

$ app --help

Usage: app -p=SPEC

Available options:

-p, --package=SPEC

Package to use

-h, --help

Prints help information

As with regular argument its adjacent variant is required by default

$ app
Error: expected --package=SPEC, pass --help for usage information

But unlike regular variant adjacent requires name and value to be separated by = only

$ app -p=htb
Options { package: "htb" }

$ app --package=bpaf
Options { package: "bpaf" }

Separating them by space results in parse failure

$ app --package htb
Error: expected --package=SPEC, got --package. Pass --help for usage information

$ app -p htb
Error: expected --package=SPEC, got -p. Pass --help for usage information

$ app --package
Error: expected --package=SPEC, got --package. Pass --help for usage information

Trait Implementations

impl<T: Clone> Clone for ParseArgument<T>

fn clone(&self) -> ParseArgument<T>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T> Parser<T> for ParseArgument<T>

where T: FromStr + 'static, <T as FromStr>::Err: Display,

fn many(self) -> ParseMany<Self>

where Self: Sized,

Consume zero or more items from a command line and collect them into a Vec

fn collect<C>(self) -> ParseCollect<Self, C, T>

where C: FromIterator<T>, Self: Sized,

Transform parser into a collection parser

fn some(self, message: &'static str) -> ParseSome<Self>

where Self: Sized + Parser<T>,

Consume one or more items from a command line and collect them into a Vec

fn optional(self) -> ParseOptional<Self>

where Self: Sized + Parser<T>,

Turn a required argument into an optional one

fn count(self) -> ParseCount<Self, T>

where Self: Sized + Parser<T>,

Count how many times the inner parser succeeds, and return that number.

fn last(self) -> ParseLast<Self>

where Self: Sized + Parser<T>,

Apply the inner parser as many times as it succeeds, return the last value

fn parse<F, R, E>(self, f: F) -> ParseWith<T, Self, F, E, R>

where Self: Sized + Parser<T>, F: Fn(T) -> Result<R, E>, E: ToString,

Apply a failing transformation to a contained value

fn map<F, R>(self, map: F) -> ParseMap<T, Self, F, R>

where Self: Sized + Parser<T>, F: Fn(T) -> R + 'static,

Apply a pure transformation to a contained value

fn guard<F>(self, check: F, message: &'static str) -> ParseGuard<Self, F>

where Self: Sized + Parser<T>, F: Fn(&T) -> bool,

Validate or fail with a message

fn fallback(self, value: T) -> ParseFallback<Self, T>

where Self: Sized + Parser<T>,

Use this value as default if the value isn’t present on a command line

fn fallback_with<F, E>(self, fallback: F) -> ParseFallbackWith<T, Self, F, E>

where Self: Sized + Parser<T>, F: Fn() -> Result<T, E>, E: ToString,

Use value produced by this function as default if the value isn’t present

fn hide(self) -> ParseHide<Self>

where Self: Sized + Parser<T>,

Ignore this parser during any sort of help generation

fn hide_usage(self) -> ParseUsage<Self>

where Self: Sized + Parser<T>,

Ignore this parser when generating a usage line

fn custom_usage<M>(self, usage: M) -> ParseUsage<Self>

where M: Into<Doc>, Self: Sized + Parser<T>,

Customize how this parser looks like in the usage line

fn group_help<M: Into<Doc>>(self, message: M) -> ParseGroupHelp<Self>

where Self: Sized + Parser<T>,

Attach a help message to a complex parser

fn with_group_help<F>(self, f: F) -> ParseWithGroupHelp<Self, F>

where Self: Sized + Parser<T>, F: Fn(MetaInfo<'_>) -> Doc,

Make a help message for a complex parser from its MetaInfo

fn complete<M, F>(self, op: F) -> ParseComp<Self, F>

where M: Into<String>, F: Fn(&T) -> Vec<(M, Option<M>)>, Self: Sized + Parser<T>,

Available on crate feature autocomplete only.

Dynamic shell completion

fn complete_shell(self, op: ShellComp) -> ParseCompShell<Self>

where Self: Sized + Parser<T>,

Available on crate feature autocomplete only.

Static shell completion

fn to_options(self) -> OptionParser<T>

where Self: Sized + Parser<T> + 'static,

Transform Parser into OptionParser to get ready to run it

fn run(self) -> T

where Self: Sized + Parser<T> + 'static,

Finalize and run the parser

fn boxed(self) -> Box<dyn Parser<T>>

where Self: Sized + Parser<T> + 'static,

Create a boxed representation for a parser