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// Std
use std::{
borrow::Cow,
collections::HashMap,
ffi::{OsStr, OsString},
iter::Map,
slice::Iter,
};
// Internal
use crate::{
args::{MatchedArg, SubCommand},
INVALID_UTF8,
};
/// Used to get information about the arguments that were supplied to the program at runtime by
/// the user. New instances of this struct are obtained by using the [`App::get_matches`] family of
/// methods.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// let matches = App::new("MyApp")
/// .arg(Arg::with_name("out")
/// .long("output")
/// .required(true)
/// .takes_value(true))
/// .arg(Arg::with_name("debug")
/// .short("d")
/// .multiple(true))
/// .arg(Arg::with_name("cfg")
/// .short("c")
/// .takes_value(true))
/// .get_matches(); // builds the instance of ArgMatches
///
/// // to get information about the "cfg" argument we created, such as the value supplied we use
/// // various ArgMatches methods, such as ArgMatches::value_of
/// if let Some(c) = matches.value_of("cfg") {
/// println!("Value for -c: {}", c);
/// }
///
/// // The ArgMatches::value_of method returns an Option because the user may not have supplied
/// // that argument at runtime. But if we specified that the argument was "required" as we did
/// // with the "out" argument, we can safely unwrap because `clap` verifies that was actually
/// // used at runtime.
/// println!("Value for --output: {}", matches.value_of("out").unwrap());
///
/// // You can check the presence of an argument
/// if matches.is_present("out") {
/// // Another way to check if an argument was present, or if it occurred multiple times is to
/// // use occurrences_of() which returns 0 if an argument isn't found at runtime, or the
/// // number of times that it occurred, if it was. To allow an argument to appear more than
/// // once, you must use the .multiple(true) method, otherwise it will only return 1 or 0.
/// if matches.occurrences_of("debug") > 2 {
/// println!("Debug mode is REALLY on, don't be crazy");
/// } else {
/// println!("Debug mode kind of on");
/// }
/// }
/// ```
/// [`App::get_matches`]: ./struct.App.html#method.get_matches
#[derive(Debug, Clone)]
pub struct ArgMatches<'a> {
#[doc(hidden)]
pub args: HashMap<&'a str, MatchedArg>,
#[doc(hidden)]
pub subcommand: Option<Box<SubCommand<'a>>>,
#[doc(hidden)]
pub usage: Option<String>,
}
impl<'a> Default for ArgMatches<'a> {
fn default() -> Self {
ArgMatches {
args: HashMap::new(),
subcommand: None,
usage: None,
}
}
}
impl<'a> ArgMatches<'a> {
#[doc(hidden)]
pub fn new() -> Self {
ArgMatches {
..Default::default()
}
}
/// Gets the value of a specific [option] or [positional] argument (i.e. an argument that takes
/// an additional value at runtime). If the option wasn't present at runtime
/// it returns `None`.
///
/// *NOTE:* If getting a value for an option or positional argument that allows multiples,
/// prefer [`ArgMatches::values_of`] as `ArgMatches::value_of` will only return the *first*
/// value.
///
/// # Panics
///
/// This method will [`panic!`] if the value contains invalid UTF-8 code points.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myapp")
/// .arg(Arg::with_name("output")
/// .takes_value(true))
/// .get_matches_from(vec!["myapp", "something"]);
///
/// assert_eq!(m.value_of("output"), Some("something"));
/// ```
/// [option]: ./struct.Arg.html#method.takes_value
/// [positional]: ./struct.Arg.html#method.index
/// [`ArgMatches::values_of`]: ./struct.ArgMatches.html#method.values_of
pub fn value_of<S: AsRef<str>>(&self, name: S) -> Option<&str> {
if let Some(arg) = self.args.get(name.as_ref()) {
if let Some(v) = arg.vals.get(0) {
return Some(v.to_str().expect(INVALID_UTF8));
}
}
None
}
/// Gets the lossy value of a specific argument. If the argument wasn't present at runtime
/// it returns `None`. A lossy value is one which contains invalid UTF-8 code points, those
/// invalid points will be replaced with `\u{FFFD}`
///
/// *NOTE:* If getting a value for an option or positional argument that allows multiples,
/// prefer [`Arg::values_of_lossy`] as `value_of_lossy()` will only return the *first* value.
///
/// # Examples
///
#[cfg_attr(not(unix), doc = " ```ignore")]
#[cfg_attr(unix, doc = " ```")]
/// # use clap::{App, Arg};
/// use std::ffi::OsString;
/// use std::os::unix::ffi::{OsStrExt,OsStringExt};
///
/// let m = App::new("utf8")
/// .arg(Arg::from_usage("<arg> 'some arg'"))
/// .get_matches_from(vec![OsString::from("myprog"),
/// // "Hi {0xe9}!"
/// OsString::from_vec(vec![b'H', b'i', b' ', 0xe9, b'!'])]);
/// assert_eq!(&*m.value_of_lossy("arg").unwrap(), "Hi \u{FFFD}!");
/// ```
/// [`Arg::values_of_lossy`]: ./struct.ArgMatches.html#method.values_of_lossy
pub fn value_of_lossy<S: AsRef<str>>(&'a self, name: S) -> Option<Cow<'a, str>> {
if let Some(arg) = self.args.get(name.as_ref()) {
if let Some(v) = arg.vals.get(0) {
return Some(v.to_string_lossy());
}
}
None
}
/// Gets the OS version of a string value of a specific argument. If the option wasn't present
/// at runtime it returns `None`. An OS value on Unix-like systems is any series of bytes,
/// regardless of whether or not they contain valid UTF-8 code points. Since [`String`]s in
/// Rust are guaranteed to be valid UTF-8, a valid filename on a Unix system as an argument
/// value may contain invalid UTF-8 code points.
///
/// *NOTE:* If getting a value for an option or positional argument that allows multiples,
/// prefer [`ArgMatches::values_of_os`] as `Arg::value_of_os` will only return the *first*
/// value.
///
/// # Examples
///
#[cfg_attr(not(unix), doc = " ```ignore")]
#[cfg_attr(unix, doc = " ```")]
/// # use clap::{App, Arg};
/// use std::ffi::OsString;
/// use std::os::unix::ffi::{OsStrExt,OsStringExt};
///
/// let m = App::new("utf8")
/// .arg(Arg::from_usage("<arg> 'some arg'"))
/// .get_matches_from(vec![OsString::from("myprog"),
/// // "Hi {0xe9}!"
/// OsString::from_vec(vec![b'H', b'i', b' ', 0xe9, b'!'])]);
/// assert_eq!(&*m.value_of_os("arg").unwrap().as_bytes(), [b'H', b'i', b' ', 0xe9, b'!']);
/// ```
/// [`ArgMatches::values_of_os`]: ./struct.ArgMatches.html#method.values_of_os
pub fn value_of_os<S: AsRef<str>>(&self, name: S) -> Option<&OsStr> {
self.args
.get(name.as_ref())
.and_then(|arg| arg.vals.get(0).map(|v| v.as_os_str()))
}
/// Gets a [`Values`] struct which implements [`Iterator`] for values of a specific argument
/// (i.e. an argument that takes multiple values at runtime). If the option wasn't present at
/// runtime it returns `None`
///
/// # Panics
///
/// This method will panic if any of the values contain invalid UTF-8 code points.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myprog")
/// .arg(Arg::with_name("output")
/// .multiple(true)
/// .short("o")
/// .takes_value(true))
/// .get_matches_from(vec![
/// "myprog", "-o", "val1", "val2", "val3"
/// ]);
/// let vals: Vec<&str> = m.values_of("output").unwrap().collect();
/// assert_eq!(vals, ["val1", "val2", "val3"]);
/// ```
/// [`Values`]: ./struct.Values.html
pub fn values_of<S: AsRef<str>>(&'a self, name: S) -> Option<Values<'a>> {
if let Some(arg) = self.args.get(name.as_ref()) {
fn to_str_slice(o: &OsString) -> &str {
o.to_str().expect(INVALID_UTF8)
}
let to_str_slice: fn(&OsString) -> &str = to_str_slice; // coerce to fn pointer
return Some(Values {
iter: arg.vals.iter().map(to_str_slice),
});
}
None
}
/// Gets the lossy values of a specific argument. If the option wasn't present at runtime
/// it returns `None`. A lossy value is one where if it contains invalid UTF-8 code points,
/// those invalid points will be replaced with `\u{FFFD}`
///
/// # Examples
///
#[cfg_attr(not(unix), doc = " ```ignore")]
#[cfg_attr(unix, doc = " ```")]
/// # use clap::{App, Arg};
/// use std::ffi::OsString;
/// use std::os::unix::ffi::OsStringExt;
///
/// let m = App::new("utf8")
/// .arg(Arg::from_usage("<arg>... 'some arg'"))
/// .get_matches_from(vec![OsString::from("myprog"),
/// // "Hi"
/// OsString::from_vec(vec![b'H', b'i']),
/// // "{0xe9}!"
/// OsString::from_vec(vec![0xe9, b'!'])]);
/// let mut itr = m.values_of_lossy("arg").unwrap().into_iter();
/// assert_eq!(&itr.next().unwrap()[..], "Hi");
/// assert_eq!(&itr.next().unwrap()[..], "\u{FFFD}!");
/// assert_eq!(itr.next(), None);
/// ```
pub fn values_of_lossy<S: AsRef<str>>(&'a self, name: S) -> Option<Vec<String>> {
if let Some(arg) = self.args.get(name.as_ref()) {
return Some(
arg.vals
.iter()
.map(|v| v.to_string_lossy().into_owned())
.collect(),
);
}
None
}
/// Gets a [`OsValues`] struct which is implements [`Iterator`] for [`OsString`] values of a
/// specific argument. If the option wasn't present at runtime it returns `None`. An OS value
/// on Unix-like systems is any series of bytes, regardless of whether or not they contain
/// valid UTF-8 code points. Since [`String`]s in Rust are guaranteed to be valid UTF-8, a valid
/// filename as an argument value on Linux (for example) may contain invalid UTF-8 code points.
///
/// # Examples
///
#[cfg_attr(not(unix), doc = " ```ignore")]
#[cfg_attr(unix, doc = " ```")]
/// # use clap::{App, Arg};
/// use std::ffi::{OsStr,OsString};
/// use std::os::unix::ffi::{OsStrExt,OsStringExt};
///
/// let m = App::new("utf8")
/// .arg(Arg::from_usage("<arg>... 'some arg'"))
/// .get_matches_from(vec![OsString::from("myprog"),
/// // "Hi"
/// OsString::from_vec(vec![b'H', b'i']),
/// // "{0xe9}!"
/// OsString::from_vec(vec![0xe9, b'!'])]);
///
/// let mut itr = m.values_of_os("arg").unwrap().into_iter();
/// assert_eq!(itr.next(), Some(OsStr::new("Hi")));
/// assert_eq!(itr.next(), Some(OsStr::from_bytes(&[0xe9, b'!'])));
/// assert_eq!(itr.next(), None);
/// ```
/// [`OsValues`]: ./struct.OsValues.html
pub fn values_of_os<S: AsRef<str>>(&'a self, name: S) -> Option<OsValues<'a>> {
fn to_str_slice(o: &OsString) -> &OsStr {
&*o
}
let to_str_slice: fn(&'a OsString) -> &'a OsStr = to_str_slice; // coerce to fn pointer
if let Some(arg) = self.args.get(name.as_ref()) {
return Some(OsValues {
iter: arg.vals.iter().map(to_str_slice),
});
}
None
}
/// Returns `true` if an argument was present at runtime, otherwise `false`.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myprog")
/// .arg(Arg::with_name("debug")
/// .short("d"))
/// .get_matches_from(vec![
/// "myprog", "-d"
/// ]);
///
/// assert!(m.is_present("debug"));
/// ```
pub fn is_present<S: AsRef<str>>(&self, name: S) -> bool {
if let Some(ref sc) = self.subcommand {
if sc.name == name.as_ref() {
return true;
}
}
self.args.contains_key(name.as_ref())
}
/// Returns the number of times an argument was used at runtime. If an argument isn't present
/// it will return `0`.
///
/// **NOTE:** This returns the number of times the argument was used, *not* the number of
/// values. For example, `-o val1 val2 val3 -o val4` would return `2` (2 occurrences, but 4
/// values).
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myprog")
/// .arg(Arg::with_name("debug")
/// .short("d")
/// .multiple(true))
/// .get_matches_from(vec![
/// "myprog", "-d", "-d", "-d"
/// ]);
///
/// assert_eq!(m.occurrences_of("debug"), 3);
/// ```
///
/// This next example shows that counts actual uses of the argument, not just `-`'s
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myprog")
/// .arg(Arg::with_name("debug")
/// .short("d")
/// .multiple(true))
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .get_matches_from(vec![
/// "myprog", "-ddfd"
/// ]);
///
/// assert_eq!(m.occurrences_of("debug"), 3);
/// assert_eq!(m.occurrences_of("flag"), 1);
/// ```
pub fn occurrences_of<S: AsRef<str>>(&self, name: S) -> u64 {
self.args.get(name.as_ref()).map_or(0, |a| a.occurs)
}
/// Gets the starting index of the argument in respect to all other arguments. Indices are
/// similar to argv indices, but are not exactly 1:1.
///
/// For flags (i.e. those arguments which don't have an associated value), indices refer
/// to occurrence of the switch, such as `-f`, or `--flag`. However, for options the indices
/// refer to the *values* `-o val` would therefore not represent two distinct indices, only the
/// index for `val` would be recorded. This is by design.
///
/// Besides the flag/option descrepancy, the primary difference between an argv index and clap
/// index, is that clap continues counting once all arguments have properly seperated, whereas
/// an argv index does not.
///
/// The examples should clear this up.
///
/// *NOTE:* If an argument is allowed multiple times, this method will only give the *first*
/// index.
///
/// # Examples
///
/// The argv indices are listed in the comments below. See how they correspond to the clap
/// indices. Note that if it's not listed in a clap index, this is becuase it's not saved in
/// in an `ArgMatches` struct for querying.
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myapp")
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .arg(Arg::with_name("option")
/// .short("o")
/// .takes_value(true))
/// .get_matches_from(vec!["myapp", "-f", "-o", "val"]);
/// // ARGV idices: ^0 ^1 ^2 ^3
/// // clap idices: ^1 ^3
///
/// assert_eq!(m.index_of("flag"), Some(1));
/// assert_eq!(m.index_of("option"), Some(3));
/// ```
///
/// Now notice, if we use one of the other styles of options:
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myapp")
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .arg(Arg::with_name("option")
/// .short("o")
/// .takes_value(true))
/// .get_matches_from(vec!["myapp", "-f", "-o=val"]);
/// // ARGV idices: ^0 ^1 ^2
/// // clap idices: ^1 ^3
///
/// assert_eq!(m.index_of("flag"), Some(1));
/// assert_eq!(m.index_of("option"), Some(3));
/// ```
///
/// Things become much more complicated, or clear if we look at a more complex combination of
/// flags. Let's also throw in the final option style for good measure.
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myapp")
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .arg(Arg::with_name("flag2")
/// .short("F"))
/// .arg(Arg::with_name("flag3")
/// .short("z"))
/// .arg(Arg::with_name("option")
/// .short("o")
/// .takes_value(true))
/// .get_matches_from(vec!["myapp", "-fzF", "-oval"]);
/// // ARGV idices: ^0 ^1 ^2
/// // clap idices: ^1,2,3 ^5
/// //
/// // clap sees the above as 'myapp -f -z -F -o val'
/// // ^0 ^1 ^2 ^3 ^4 ^5
/// assert_eq!(m.index_of("flag"), Some(1));
/// assert_eq!(m.index_of("flag2"), Some(3));
/// assert_eq!(m.index_of("flag3"), Some(2));
/// assert_eq!(m.index_of("option"), Some(5));
/// ```
///
/// One final combination of flags/options to see how they combine:
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myapp")
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .arg(Arg::with_name("flag2")
/// .short("F"))
/// .arg(Arg::with_name("flag3")
/// .short("z"))
/// .arg(Arg::with_name("option")
/// .short("o")
/// .takes_value(true)
/// .multiple(true))
/// .get_matches_from(vec!["myapp", "-fzFoval"]);
/// // ARGV idices: ^0 ^1
/// // clap idices: ^1,2,3^5
/// //
/// // clap sees the above as 'myapp -f -z -F -o val'
/// // ^0 ^1 ^2 ^3 ^4 ^5
/// assert_eq!(m.index_of("flag"), Some(1));
/// assert_eq!(m.index_of("flag2"), Some(3));
/// assert_eq!(m.index_of("flag3"), Some(2));
/// assert_eq!(m.index_of("option"), Some(5));
/// ```
///
/// The last part to mention is when values are sent in multiple groups with a [delimiter].
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myapp")
/// .arg(Arg::with_name("option")
/// .short("o")
/// .takes_value(true)
/// .multiple(true))
/// .get_matches_from(vec!["myapp", "-o=val1,val2,val3"]);
/// // ARGV idices: ^0 ^1
/// // clap idices: ^2 ^3 ^4
/// //
/// // clap sees the above as 'myapp -o val1 val2 val3'
/// // ^0 ^1 ^2 ^3 ^4
/// assert_eq!(m.index_of("option"), Some(2));
/// ```
/// [`ArgMatches`]: ./struct.ArgMatches.html
/// [delimiter]: ./struct.Arg.html#method.value_delimiter
pub fn index_of<S: AsRef<str>>(&self, name: S) -> Option<usize> {
if let Some(arg) = self.args.get(name.as_ref()) {
if let Some(i) = arg.indices.get(0) {
return Some(*i);
}
}
None
}
/// Gets all indices of the argument in respect to all other arguments. Indices are
/// similar to argv indices, but are not exactly 1:1.
///
/// For flags (i.e. those arguments which don't have an associated value), indices refer
/// to occurrence of the switch, such as `-f`, or `--flag`. However, for options the indices
/// refer to the *values* `-o val` would therefore not represent two distinct indices, only the
/// index for `val` would be recorded. This is by design.
///
/// *NOTE:* For more information about how clap indices compare to argv indices, see
/// [`ArgMatches::index_of`]
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myapp")
/// .arg(Arg::with_name("option")
/// .short("o")
/// .takes_value(true)
/// .use_delimiter(true)
/// .multiple(true))
/// .get_matches_from(vec!["myapp", "-o=val1,val2,val3"]);
/// // ARGV idices: ^0 ^1
/// // clap idices: ^2 ^3 ^4
/// //
/// // clap sees the above as 'myapp -o val1 val2 val3'
/// // ^0 ^1 ^2 ^3 ^4
/// assert_eq!(m.indices_of("option").unwrap().collect::<Vec<_>>(), &[2, 3, 4]);
/// ```
///
/// Another quick example is when flags and options are used together
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myapp")
/// .arg(Arg::with_name("option")
/// .short("o")
/// .takes_value(true)
/// .multiple(true))
/// .arg(Arg::with_name("flag")
/// .short("f")
/// .multiple(true))
/// .get_matches_from(vec!["myapp", "-o", "val1", "-f", "-o", "val2", "-f"]);
/// // ARGV idices: ^0 ^1 ^2 ^3 ^4 ^5 ^6
/// // clap idices: ^2 ^3 ^5 ^6
///
/// assert_eq!(m.indices_of("option").unwrap().collect::<Vec<_>>(), &[2, 5]);
/// assert_eq!(m.indices_of("flag").unwrap().collect::<Vec<_>>(), &[3, 6]);
/// ```
///
/// One final example, which is an odd case; if we *don't* use value delimiter as we did with
/// the first example above instead of `val1`, `val2` and `val3` all being distinc values, they
/// would all be a single value of `val1,val2,val3`, in which case case they'd only receive a
/// single index.
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myapp")
/// .arg(Arg::with_name("option")
/// .short("o")
/// .takes_value(true)
/// .multiple(true))
/// .get_matches_from(vec!["myapp", "-o=val1,val2,val3"]);
/// // ARGV idices: ^0 ^1
/// // clap idices: ^2
/// //
/// // clap sees the above as 'myapp -o "val1,val2,val3"'
/// // ^0 ^1 ^2
/// assert_eq!(m.indices_of("option").unwrap().collect::<Vec<_>>(), &[2]);
/// ```
/// [`ArgMatches`]: ./struct.ArgMatches.html
/// [`ArgMatches::index_of`]: ./struct.ArgMatches.html#method.index_of
/// [delimiter]: ./struct.Arg.html#method.value_delimiter
pub fn indices_of<S: AsRef<str>>(&'a self, name: S) -> Option<Indices<'a>> {
if let Some(arg) = self.args.get(name.as_ref()) {
fn to_usize(i: &usize) -> usize {
*i
}
let to_usize: fn(&usize) -> usize = to_usize; // coerce to fn pointer
return Some(Indices {
iter: arg.indices.iter().map(to_usize),
});
}
None
}
/// Because [`Subcommand`]s are essentially "sub-[`App`]s" they have their own [`ArgMatches`]
/// as well. This method returns the [`ArgMatches`] for a particular subcommand or `None` if
/// the subcommand wasn't present at runtime.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg, SubCommand};
/// let app_m = App::new("myprog")
/// .arg(Arg::with_name("debug")
/// .short("d"))
/// .subcommand(SubCommand::with_name("test")
/// .arg(Arg::with_name("opt")
/// .long("option")
/// .takes_value(true)))
/// .get_matches_from(vec![
/// "myprog", "-d", "test", "--option", "val"
/// ]);
///
/// // Both parent commands, and child subcommands can have arguments present at the same times
/// assert!(app_m.is_present("debug"));
///
/// // Get the subcommand's ArgMatches instance
/// if let Some(sub_m) = app_m.subcommand_matches("test") {
/// // Use the struct like normal
/// assert_eq!(sub_m.value_of("opt"), Some("val"));
/// }
/// ```
/// [`Subcommand`]: ./struct.SubCommand.html
/// [`App`]: ./struct.App.html
/// [`ArgMatches`]: ./struct.ArgMatches.html
pub fn subcommand_matches<S: AsRef<str>>(&self, name: S) -> Option<&ArgMatches<'a>> {
if let Some(ref s) = self.subcommand {
if s.name == name.as_ref() {
return Some(&s.matches);
}
}
None
}
/// Because [`Subcommand`]s are essentially "sub-[`App`]s" they have their own [`ArgMatches`]
/// as well.But simply getting the sub-[`ArgMatches`] doesn't help much if we don't also know
/// which subcommand was actually used. This method returns the name of the subcommand that was
/// used at runtime, or `None` if one wasn't.
///
/// *NOTE*: Subcommands form a hierarchy, where multiple subcommands can be used at runtime,
/// but only a single subcommand from any group of sibling commands may used at once.
///
/// An ASCII art depiction may help explain this better...Using a fictional version of `git` as
/// the demo subject. Imagine the following are all subcommands of `git` (note, the author is
/// aware these aren't actually all subcommands in the real `git` interface, but it makes
/// explanation easier)
///
/// ```notrust
/// Top Level App (git) TOP
/// |
/// -----------------------------------------
/// / | \ \
/// clone push add commit LEVEL 1
/// | / \ / \ |
/// url origin remote ref name message LEVEL 2
/// / /\
/// path remote local LEVEL 3
/// ```
///
/// Given the above fictional subcommand hierarchy, valid runtime uses would be (not an all
/// inclusive list, and not including argument options per command for brevity and clarity):
///
/// ```sh
/// $ git clone url
/// $ git push origin path
/// $ git add ref local
/// $ git commit message
/// ```
///
/// Notice only one command per "level" may be used. You could not, for example, do `$ git
/// clone url push origin path`
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg, SubCommand};
/// let app_m = App::new("git")
/// .subcommand(SubCommand::with_name("clone"))
/// .subcommand(SubCommand::with_name("push"))
/// .subcommand(SubCommand::with_name("commit"))
/// .get_matches();
///
/// match app_m.subcommand_name() {
/// Some("clone") => {}, // clone was used
/// Some("push") => {}, // push was used
/// Some("commit") => {}, // commit was used
/// _ => {}, // Either no subcommand or one not tested for...
/// }
/// ```
/// [`Subcommand`]: ./struct.SubCommand.html
/// [`App`]: ./struct.App.html
/// [`ArgMatches`]: ./struct.ArgMatches.html
pub fn subcommand_name(&self) -> Option<&str> {
self.subcommand.as_ref().map(|sc| &sc.name[..])
}
/// This brings together [`ArgMatches::subcommand_matches`] and [`ArgMatches::subcommand_name`]
/// by returning a tuple with both pieces of information.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg, SubCommand};
/// let app_m = App::new("git")
/// .subcommand(SubCommand::with_name("clone"))
/// .subcommand(SubCommand::with_name("push"))
/// .subcommand(SubCommand::with_name("commit"))
/// .get_matches();
///
/// match app_m.subcommand() {
/// ("clone", Some(sub_m)) => {}, // clone was used
/// ("push", Some(sub_m)) => {}, // push was used
/// ("commit", Some(sub_m)) => {}, // commit was used
/// _ => {}, // Either no subcommand or one not tested for...
/// }
/// ```
///
/// Another useful scenario is when you want to support third party, or external, subcommands.
/// In these cases you can't know the subcommand name ahead of time, so use a variable instead
/// with pattern matching!
///
/// ```rust
/// # use clap::{App, AppSettings};
/// // Assume there is an external subcommand named "subcmd"
/// let app_m = App::new("myprog")
/// .setting(AppSettings::AllowExternalSubcommands)
/// .get_matches_from(vec![
/// "myprog", "subcmd", "--option", "value", "-fff", "--flag"
/// ]);
///
/// // All trailing arguments will be stored under the subcommand's sub-matches using an empty
/// // string argument name
/// match app_m.subcommand() {
/// (external, Some(sub_m)) => {
/// let ext_args: Vec<&str> = sub_m.values_of("").unwrap().collect();
/// assert_eq!(external, "subcmd");
/// assert_eq!(ext_args, ["--option", "value", "-fff", "--flag"]);
/// },
/// _ => {},
/// }
/// ```
/// [`ArgMatches::subcommand_matches`]: ./struct.ArgMatches.html#method.subcommand_matches
/// [`ArgMatches::subcommand_name`]: ./struct.ArgMatches.html#method.subcommand_name
pub fn subcommand(&self) -> (&str, Option<&ArgMatches<'a>>) {
self.subcommand
.as_ref()
.map_or(("", None), |sc| (&sc.name[..], Some(&sc.matches)))
}
/// Returns a string slice of the usage statement for the [`App`] or [`SubCommand`]
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg, SubCommand};
/// let app_m = App::new("myprog")
/// .subcommand(SubCommand::with_name("test"))
/// .get_matches();
///
/// println!("{}", app_m.usage());
/// ```
/// [`Subcommand`]: ./struct.SubCommand.html
/// [`App`]: ./struct.App.html
pub fn usage(&self) -> &str {
self.usage.as_ref().map_or("", |u| &u[..])
}
}
// The following were taken and adapated from vec_map source
// commit: be5e1fa3c26e351761b33010ddbdaf5f05dbcc33
// license: MIT - Copyright (c) 2015 The Rust Project Developers
/// An iterator for getting multiple values out of an argument via the [`ArgMatches::values_of`]
/// method.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myapp")
/// .arg(Arg::with_name("output")
/// .short("o")
/// .multiple(true)
/// .takes_value(true))
/// .get_matches_from(vec!["myapp", "-o", "val1", "val2"]);
///
/// let mut values = m.values_of("output").unwrap();
///
/// assert_eq!(values.next(), Some("val1"));
/// assert_eq!(values.next(), Some("val2"));
/// assert_eq!(values.next(), None);
/// ```
/// [`ArgMatches::values_of`]: ./struct.ArgMatches.html#method.values_of
#[derive(Debug, Clone)]
pub struct Values<'a> {
iter: Map<Iter<'a, OsString>, fn(&'a OsString) -> &'a str>,
}
impl<'a> Iterator for Values<'a> {
type Item = &'a str;
fn next(&mut self) -> Option<&'a str> {
self.iter.next()
}
fn size_hint(&self) -> (usize, Option<usize>) {
self.iter.size_hint()
}
}
impl<'a> DoubleEndedIterator for Values<'a> {
fn next_back(&mut self) -> Option<&'a str> {
self.iter.next_back()
}
}
impl<'a> ExactSizeIterator for Values<'a> {}
/// Creates an empty iterator.
impl<'a> Default for Values<'a> {
fn default() -> Self {
static EMPTY: [OsString; 0] = [];
// This is never called because the iterator is empty:
fn to_str_slice(_: &OsString) -> &str {
unreachable!()
}
Values {
iter: EMPTY[..].iter().map(to_str_slice),
}
}
}
/// An iterator for getting multiple values out of an argument via the [`ArgMatches::values_of_os`]
/// method. Usage of this iterator allows values which contain invalid UTF-8 code points unlike
/// [`Values`].
///
/// # Examples
///
#[cfg_attr(not(unix), doc = " ```ignore")]
#[cfg_attr(unix, doc = " ```")]
/// # use clap::{App, Arg};
/// use std::ffi::OsString;
/// use std::os::unix::ffi::{OsStrExt,OsStringExt};
///
/// let m = App::new("utf8")
/// .arg(Arg::from_usage("<arg> 'some arg'"))
/// .get_matches_from(vec![OsString::from("myprog"),
/// // "Hi {0xe9}!"
/// OsString::from_vec(vec![b'H', b'i', b' ', 0xe9, b'!'])]);
/// assert_eq!(&*m.value_of_os("arg").unwrap().as_bytes(), [b'H', b'i', b' ', 0xe9, b'!']);
/// ```
/// [`ArgMatches::values_of_os`]: ./struct.ArgMatches.html#method.values_of_os
/// [`Values`]: ./struct.Values.html
#[derive(Debug, Clone)]
pub struct OsValues<'a> {
iter: Map<Iter<'a, OsString>, fn(&'a OsString) -> &'a OsStr>,
}
impl<'a> Iterator for OsValues<'a> {
type Item = &'a OsStr;
fn next(&mut self) -> Option<&'a OsStr> {
self.iter.next()
}
fn size_hint(&self) -> (usize, Option<usize>) {
self.iter.size_hint()
}
}
impl<'a> DoubleEndedIterator for OsValues<'a> {
fn next_back(&mut self) -> Option<&'a OsStr> {
self.iter.next_back()
}
}
impl<'a> ExactSizeIterator for OsValues<'a> {}
/// Creates an empty iterator.
impl<'a> Default for OsValues<'a> {
fn default() -> Self {
static EMPTY: [OsString; 0] = [];
// This is never called because the iterator is empty:
fn to_str_slice(_: &OsString) -> &OsStr {
unreachable!()
}
OsValues {
iter: EMPTY[..].iter().map(to_str_slice),
}
}
}
/// An iterator for getting multiple indices out of an argument via the [`ArgMatches::indices_of`]
/// method.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("myapp")
/// .arg(Arg::with_name("output")
/// .short("o")
/// .multiple(true)
/// .takes_value(true))
/// .get_matches_from(vec!["myapp", "-o", "val1", "val2"]);
///
/// let mut indices = m.indices_of("output").unwrap();
///
/// assert_eq!(indices.next(), Some(2));
/// assert_eq!(indices.next(), Some(3));
/// assert_eq!(indices.next(), None);
/// ```
/// [`ArgMatches::indices_of`]: ./struct.ArgMatches.html#method.indices_of
#[derive(Debug, Clone)]
pub struct Indices<'a> {
iter: Map<Iter<'a, usize>, fn(&'a usize) -> usize>,
}
impl<'a> Iterator for Indices<'a> {
type Item = usize;
fn next(&mut self) -> Option<usize> {
self.iter.next()
}
fn size_hint(&self) -> (usize, Option<usize>) {
self.iter.size_hint()
}
}
impl<'a> DoubleEndedIterator for Indices<'a> {
fn next_back(&mut self) -> Option<usize> {
self.iter.next_back()
}
}
impl<'a> ExactSizeIterator for Indices<'a> {}
/// Creates an empty iterator.
impl<'a> Default for Indices<'a> {
fn default() -> Self {
static EMPTY: [usize; 0] = [];
// This is never called because the iterator is empty:
fn to_usize(_: &usize) -> usize {
unreachable!()
}
Indices {
iter: EMPTY[..].iter().map(to_usize),
}
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_default_values() {
let mut values: Values = Values::default();
assert_eq!(values.next(), None);
}
#[test]
fn test_default_values_with_shorter_lifetime() {
let matches = ArgMatches::new();
let mut values = matches.values_of("").unwrap_or_default();
assert_eq!(values.next(), None);
}
#[test]
fn test_default_osvalues() {
let mut values: OsValues = OsValues::default();
assert_eq!(values.next(), None);
}
#[test]
fn test_default_osvalues_with_shorter_lifetime() {
let matches = ArgMatches::new();
let mut values = matches.values_of_os("").unwrap_or_default();
assert_eq!(values.next(), None);
}
#[test]
fn test_default_indices() {
let mut indices: Indices = Indices::default();
assert_eq!(indices.next(), None);
}
#[test]
fn test_default_indices_with_shorter_lifetime() {
let matches = ArgMatches::new();
let mut indices = matches.indices_of("").unwrap_or_default();
assert_eq!(indices.next(), None);
}
}