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mod help;
mod meta;
pub mod parser;
mod settings;
mod usage;
mod validator;
// Std
use std::result::Result as StdResult;
use std::{
env,
ffi::{OsStr, OsString},
fmt,
io::{self, BufRead, BufWriter, Write},
path::Path,
process,
rc::Rc,
};
// Third Party
#[cfg(feature = "yaml")]
use yaml_rust::Yaml;
// Internal
use crate::errors::Result as ClapResult;
use crate::{
app::{help::Help, parser::Parser},
args::{AnyArg, Arg, ArgGroup, ArgMatcher, ArgMatches, ArgSettings},
completions::Shell,
map::{self, VecMap},
};
pub use settings::AppSettings;
/// Used to create a representation of a command line program and all possible command line
/// arguments. Application settings are set using the "builder pattern" with the
/// [`App::get_matches`] family of methods being the terminal methods that starts the
/// runtime-parsing process. These methods then return information about the user supplied
/// arguments (or lack there of).
///
/// **NOTE:** There aren't any mandatory "options" that one must set. The "options" may
/// also appear in any order (so long as one of the [`App::get_matches`] methods is the last method
/// called).
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// let m = App::new("My Program")
/// .author("Me, me@mail.com")
/// .version("1.0.2")
/// .about("Explains in brief what the program does")
/// .arg(
/// Arg::with_name("in_file").index(1)
/// )
/// .after_help("Longer explanation to appear after the options when \
/// displaying the help information from --help or -h")
/// .get_matches();
///
/// // Your program logic starts here...
/// ```
/// [`App::get_matches`]: ./struct.App.html#method.get_matches
#[allow(missing_debug_implementations)]
pub struct App<'a, 'b>
where
'a: 'b,
{
#[doc(hidden)]
pub p: Parser<'a, 'b>,
}
impl<'a, 'b> App<'a, 'b> {
/// Creates a new instance of an application requiring a name. The name may be, but doesn't
/// have to be same as the binary. The name will be displayed to the user when they request to
/// print version or help and usage information.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// let prog = App::new("My Program")
/// # ;
/// ```
pub fn new<S: Into<String>>(n: S) -> Self {
App {
p: Parser::with_name(n.into()),
}
}
/// Get the name of the app
pub fn get_name(&self) -> &str {
&self.p.meta.name
}
/// Get the name of the binary
pub fn get_bin_name(&self) -> Option<&str> {
self.p.meta.bin_name.as_deref()
}
/// Creates a new instance of an application requiring a name, but uses the [`crate_authors!`]
/// and [`crate_version!`] macros to fill in the [`App::author`] and [`App::version`] fields.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// let prog = App::with_defaults("My Program")
/// # ;
/// ```
/// [`crate_authors!`]: ./macro.crate_authors!.html
/// [`crate_version!`]: ./macro.crate_version!.html
/// [`App::author`]: ./struct.App.html#method.author
/// [`App::version`]: ./struct.App.html#method.author
#[deprecated(
since = "2.14.1",
note = "Can never work; use explicit App::author() and App::version() calls instead"
)]
pub fn with_defaults<S: Into<String>>(n: S) -> Self {
let mut a = App {
p: Parser::with_name(n.into()),
};
a.p.meta.author = Some("Kevin K. <kbknapp@gmail.com>");
a.p.meta.version = Some("2.19.2");
a
}
/// Creates a new instance of [`App`] from a .yml (YAML) file. A full example of supported YAML
/// objects can be found in [`examples/17_yaml.rs`] and [`examples/17_yaml.yml`]. One great use
/// for using YAML is when supporting multiple languages and dialects, as each language could
/// be a distinct YAML file and determined at compiletime via `cargo` "features" in your
/// `Cargo.toml`
///
/// In order to use this function you must compile `clap` with the `features = ["yaml"]` in
/// your settings for the `[dependencies.clap]` table of your `Cargo.toml`
///
/// **NOTE:** Due to how the YAML objects are built there is a convenience macro for loading
/// the YAML file at compile time (relative to the current file, like modules work). That YAML
/// object can then be passed to this function.
///
/// # Panics
///
/// The YAML file must be properly formatted or this function will [`panic!`]. A good way to
/// ensure this doesn't happen is to run your program with the `--help` switch. If this passes
/// without error, you needn't worry because the YAML is properly formatted.
///
/// # Examples
///
/// The following example shows how to load a properly formatted YAML file to build an instance
/// of an [`App`] struct.
///
/// ```ignore
/// # #[macro_use]
/// # extern crate clap;
/// # use clap::App;
/// # fn main() {
/// let yml = load_yaml!("app.yml");
/// let app = App::from_yaml(yml);
///
/// // continued logic goes here, such as `app.get_matches()` etc.
/// # }
/// ```
/// [`App`]: ./struct.App.html
/// [`examples/17_yaml.rs`]: https://github.com/clap-rs/clap/blob/v2.33.1/examples/17_yaml.rs
/// [`examples/17_yaml.yml`]: https://github.com/clap-rs/clap/blob/v2.33.1/examples/17_yaml.yml
/// [`panic!`]: https://doc.rust-lang.org/std/macro.panic!.html
#[cfg(feature = "yaml")]
pub fn from_yaml(yaml: &'a Yaml) -> App<'a, 'a> {
App::from(yaml)
}
/// Sets a string of author(s) that will be displayed to the user when they
/// request the help information with `--help` or `-h`.
///
/// **Pro-tip:** Use `clap`s convenience macro [`crate_authors!`] to automatically set your
/// application's author(s) to the same thing as your crate at compile time. See the [`examples/`]
/// directory for more information
///
/// See the [`examples/`]
/// directory for more information
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .author("Me, me@mymain.com")
/// # ;
/// ```
/// [`crate_authors!`]: ./macro.crate_authors!.html
/// [`examples/`]: https://github.com/clap-rs/clap/tree/v2.33.1/examples
pub fn author<S: Into<&'b str>>(mut self, author: S) -> Self {
self.p.meta.author = Some(author.into());
self
}
/// Overrides the system-determined binary name. This should only be used when absolutely
/// necessary, such as when the binary name for your application is misleading, or perhaps
/// *not* how the user should invoke your program.
///
/// **Pro-tip:** When building things such as third party `cargo` subcommands, this setting
/// **should** be used!
///
/// **NOTE:** This command **should not** be used for [`SubCommand`]s.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("My Program")
/// .bin_name("my_binary")
/// # ;
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
pub fn bin_name<S: Into<String>>(mut self, name: S) -> Self {
self.p.meta.bin_name = Some(name.into());
self
}
/// Sets a string describing what the program does. This will be displayed when displaying help
/// information with `-h`.
///
/// **NOTE:** If only `about` is provided, and not [`App::long_about`] but the user requests
/// `--help` clap will still display the contents of `about` appropriately
///
/// **NOTE:** Only [`App::about`] is used in completion script generation in order to be
/// concise
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .about("Does really amazing things to great people")
/// # ;
/// ```
/// [`App::long_about`]: ./struct.App.html#method.long_about
pub fn about<S: Into<&'b str>>(mut self, about: S) -> Self {
self.p.meta.about = Some(about.into());
self
}
/// Sets a string describing what the program does. This will be displayed when displaying help
/// information.
///
/// **NOTE:** If only `long_about` is provided, and not [`App::about`] but the user requests
/// `-h` clap will still display the contents of `long_about` appropriately
///
/// **NOTE:** Only [`App::about`] is used in completion script generation in order to be
/// concise
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .long_about(
/// "Does really amazing things to great people. Now let's talk a little
/// more in depth about how this subcommand really works. It may take about
/// a few lines of text, but that's ok!")
/// # ;
/// ```
/// [`App::about`]: ./struct.App.html#method.about
pub fn long_about<S: Into<&'b str>>(mut self, about: S) -> Self {
self.p.meta.long_about = Some(about.into());
self
}
/// Sets the program's name. This will be displayed when displaying help information.
///
/// **Pro-top:** This function is particularly useful when configuring a program via
/// [`App::from_yaml`] in conjunction with the [`crate_name!`] macro to derive the program's
/// name from its `Cargo.toml`.
///
/// # Examples
/// ```ignore
/// # #[macro_use]
/// # extern crate clap;
/// # use clap::App;
/// # fn main() {
/// let yml = load_yaml!("app.yml");
/// let app = App::from_yaml(yml)
/// .name(crate_name!());
///
/// // continued logic goes here, such as `app.get_matches()` etc.
/// # }
/// ```
///
/// [`App::from_yaml`]: ./struct.App.html#method.from_yaml
/// [`crate_name!`]: ./macro.crate_name.html
pub fn name<S: Into<String>>(mut self, name: S) -> Self {
self.p.meta.name = name.into();
self
}
/// Adds additional help information to be displayed in addition to auto-generated help. This
/// information is displayed **after** the auto-generated help information. This is often used
/// to describe how to use the arguments, or caveats to be noted.
///
/// # Examples
///
/// ```no_run
/// # use clap::App;
/// App::new("myprog")
/// .after_help("Does really amazing things to great people...but be careful with -R")
/// # ;
/// ```
pub fn after_help<S: Into<&'b str>>(mut self, help: S) -> Self {
self.p.meta.more_help = Some(help.into());
self
}
/// Adds additional help information to be displayed in addition to auto-generated help. This
/// information is displayed **before** the auto-generated help information. This is often used
/// for header information.
///
/// # Examples
///
/// ```no_run
/// # use clap::App;
/// App::new("myprog")
/// .before_help("Some info I'd like to appear before the help info")
/// # ;
/// ```
pub fn before_help<S: Into<&'b str>>(mut self, help: S) -> Self {
self.p.meta.pre_help = Some(help.into());
self
}
/// Sets a string of the version number to be displayed when displaying version or help
/// information with `-V`.
///
/// **NOTE:** If only `version` is provided, and not [`App::long_version`] but the user
/// requests `--version` clap will still display the contents of `version` appropriately
///
/// **Pro-tip:** Use `clap`s convenience macro [`crate_version!`] to automatically set your
/// application's version to the same thing as your crate at compile time. See the [`examples/`]
/// directory for more information
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .version("v0.1.24")
/// # ;
/// ```
/// [`crate_version!`]: ./macro.crate_version!.html
/// [`examples/`]: https://github.com/clap-rs/clap/tree/v2.33.1/examples
/// [`App::long_version`]: ./struct.App.html#method.long_version
pub fn version<S: Into<&'b str>>(mut self, ver: S) -> Self {
self.p.meta.version = Some(ver.into());
self
}
/// Sets a string of the version number to be displayed when displaying version or help
/// information with `--version`.
///
/// **NOTE:** If only `long_version` is provided, and not [`App::version`] but the user
/// requests `-V` clap will still display the contents of `long_version` appropriately
///
/// **Pro-tip:** Use `clap`s convenience macro [`crate_version!`] to automatically set your
/// application's version to the same thing as your crate at compile time. See the [`examples/`]
/// directory for more information
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .long_version(
/// "v0.1.24
/// commit: abcdef89726d
/// revision: 123
/// release: 2
/// binary: myprog")
/// # ;
/// ```
/// [`crate_version!`]: ./macro.crate_version!.html
/// [`examples/`]: https://github.com/clap-rs/clap/tree/v2.33.1/examples
/// [`App::version`]: ./struct.App.html#method.version
pub fn long_version<S: Into<&'b str>>(mut self, ver: S) -> Self {
self.p.meta.long_version = Some(ver.into());
self
}
/// Sets a custom usage string to override the auto-generated usage string.
///
/// This will be displayed to the user when errors are found in argument parsing, or when you
/// call [`ArgMatches::usage`]
///
/// **CAUTION:** Using this setting disables `clap`s "context-aware" usage strings. After this
/// setting is set, this will be the only usage string displayed to the user!
///
/// **NOTE:** You do not need to specify the "USAGE: \n\t" portion, as that will
/// still be applied by `clap`, you only need to specify the portion starting
/// with the binary name.
///
/// **NOTE:** This will not replace the entire help message, *only* the portion
/// showing the usage.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .usage("myapp [-clDas] <some_file>")
/// # ;
/// ```
/// [`ArgMatches::usage`]: ./struct.ArgMatches.html#method.usage
pub fn usage<S: Into<&'b str>>(mut self, usage: S) -> Self {
self.p.meta.usage_str = Some(usage.into());
self
}
/// Sets a custom help message and overrides the auto-generated one. This should only be used
/// when the auto-generated message does not suffice.
///
/// This will be displayed to the user when they use `--help` or `-h`
///
/// **NOTE:** This replaces the **entire** help message, so nothing will be auto-generated.
///
/// **NOTE:** This **only** replaces the help message for the current command, meaning if you
/// are using subcommands, those help messages will still be auto-generated unless you
/// specify a [`Arg::help`] for them as well.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myapp")
/// .help("myapp v1.0\n\
/// Does awesome things\n\
/// (C) me@mail.com\n\n\
///
/// USAGE: myapp <opts> <command>\n\n\
///
/// Options:\n\
/// -h, --help Display this message\n\
/// -V, --version Display version info\n\
/// -s <stuff> Do something with stuff\n\
/// -v Be verbose\n\n\
///
/// Commmands:\n\
/// help Prints this message\n\
/// work Do some work")
/// # ;
/// ```
/// [`Arg::help`]: ./struct.Arg.html#method.help
pub fn help<S: Into<&'b str>>(mut self, help: S) -> Self {
self.p.meta.help_str = Some(help.into());
self
}
/// Sets the [`short`] for the auto-generated `help` argument.
///
/// By default `clap` automatically assigns `h`, but this can be overridden if you have a
/// different argument which you'd prefer to use the `-h` short with. This can be done by
/// defining your own argument with a lowercase `h` as the [`short`].
///
/// `clap` lazily generates these `help` arguments **after** you've defined any arguments of
/// your own.
///
/// **NOTE:** Any leading `-` characters will be stripped, and only the first
/// non `-` character will be used as the [`short`] version
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .help_short("H") // Using an uppercase `H` instead of the default lowercase `h`
/// # ;
/// ```
/// [`short`]: ./struct.Arg.html#method.short
pub fn help_short<S: AsRef<str> + 'b>(mut self, s: S) -> Self {
self.p.help_short(s.as_ref());
self
}
/// Sets the [`short`] for the auto-generated `version` argument.
///
/// By default `clap` automatically assigns `V`, but this can be overridden if you have a
/// different argument which you'd prefer to use the `-V` short with. This can be done by
/// defining your own argument with an uppercase `V` as the [`short`].
///
/// `clap` lazily generates these `version` arguments **after** you've defined any arguments of
/// your own.
///
/// **NOTE:** Any leading `-` characters will be stripped, and only the first
/// non `-` character will be used as the `short` version
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .version_short("v") // Using a lowercase `v` instead of the default capital `V`
/// # ;
/// ```
/// [`short`]: ./struct.Arg.html#method.short
pub fn version_short<S: AsRef<str>>(mut self, s: S) -> Self {
self.p.version_short(s.as_ref());
self
}
/// Sets the help text for the auto-generated `help` argument.
///
/// By default `clap` sets this to `"Prints help information"`, but if you're using a
/// different convention for your help messages and would prefer a different phrasing you can
/// override it.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .help_message("Print help information") // Perhaps you want imperative help messages
///
/// # ;
/// ```
pub fn help_message<S: Into<&'a str>>(mut self, s: S) -> Self {
self.p.help_message = Some(s.into());
self
}
/// Sets the help text for the auto-generated `version` argument.
///
/// By default `clap` sets this to `"Prints version information"`, but if you're using a
/// different convention for your help messages and would prefer a different phrasing then you
/// can change it.
///
/// # Examples
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .version_message("Print version information") // Perhaps you want imperative help messages
/// # ;
/// ```
pub fn version_message<S: Into<&'a str>>(mut self, s: S) -> Self {
self.p.version_message = Some(s.into());
self
}
/// Sets the help template to be used, overriding the default format.
///
/// Tags arg given inside curly brackets.
///
/// Valid tags are:
///
/// * `{bin}` - Binary name.
/// * `{version}` - Version number.
/// * `{author}` - Author information.
/// * `{about}` - General description (from [`App::about`])
/// * `{usage}` - Automatically generated or given usage string.
/// * `{all-args}` - Help for all arguments (options, flags, positionals arguments,
/// and subcommands) including titles.
/// * `{unified}` - Unified help for options and flags. Note, you must *also* set
/// [`AppSettings::UnifiedHelpMessage`] to fully merge both options and
/// flags, otherwise the ordering is "best effort"
/// * `{flags}` - Help for flags.
/// * `{options}` - Help for options.
/// * `{positionals}` - Help for positionals arguments.
/// * `{subcommands}` - Help for subcommands.
/// * `{after-help}` - Help from [`App::after_help`]
/// * `{before-help}` - Help from [`App::before_help`]
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .version("1.0")
/// .template("{bin} ({version}) - {usage}")
/// # ;
/// ```
/// **NOTE:** The template system is, on purpose, very simple. Therefore the tags have to be
/// written in lowercase and without spacing.
///
/// [`App::about`]: ./struct.App.html#method.about
/// [`App::after_help`]: ./struct.App.html#method.after_help
/// [`App::before_help`]: ./struct.App.html#method.before_help
/// [`AppSettings::UnifiedHelpMessage`]: ./enum.AppSettings.html#variant.UnifiedHelpMessage
pub fn template<S: Into<&'b str>>(mut self, s: S) -> Self {
self.p.meta.template = Some(s.into());
self
}
/// Enables a single command, or [`SubCommand`], level settings.
///
/// See [`AppSettings`] for a full list of possibilities and examples.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg, AppSettings};
/// App::new("myprog")
/// .setting(AppSettings::SubcommandRequired)
/// .setting(AppSettings::WaitOnError)
/// # ;
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
/// [`AppSettings`]: ./enum.AppSettings.html
pub fn setting(mut self, setting: AppSettings) -> Self {
self.p.set(setting);
self
}
/// Enables multiple command, or [`SubCommand`], level settings
///
/// See [`AppSettings`] for a full list of possibilities and examples.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg, AppSettings};
/// App::new("myprog")
/// .settings(&[AppSettings::SubcommandRequired,
/// AppSettings::WaitOnError])
/// # ;
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
/// [`AppSettings`]: ./enum.AppSettings.html
pub fn settings(mut self, settings: &[AppSettings]) -> Self {
for s in settings {
self.p.set(*s);
}
self
}
/// Enables a single setting that is propagated down through all child [`SubCommand`]s.
///
/// See [`AppSettings`] for a full list of possibilities and examples.
///
/// **NOTE**: The setting is *only* propagated *down* and not up through parent commands.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg, AppSettings};
/// App::new("myprog")
/// .global_setting(AppSettings::SubcommandRequired)
/// # ;
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
/// [`AppSettings`]: ./enum.AppSettings.html
pub fn global_setting(mut self, setting: AppSettings) -> Self {
self.p.set(setting);
self.p.g_settings.set(setting);
self
}
/// Enables multiple settings which are propagated *down* through all child [`SubCommand`]s.
///
/// See [`AppSettings`] for a full list of possibilities and examples.
///
/// **NOTE**: The setting is *only* propagated *down* and not up through parent commands.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg, AppSettings};
/// App::new("myprog")
/// .global_settings(&[AppSettings::SubcommandRequired,
/// AppSettings::ColoredHelp])
/// # ;
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
/// [`AppSettings`]: ./enum.AppSettings.html
pub fn global_settings(mut self, settings: &[AppSettings]) -> Self {
for s in settings {
self.p.set(*s);
self.p.g_settings.set(*s)
}
self
}
/// Disables a single command, or [`SubCommand`], level setting.
///
/// See [`AppSettings`] for a full list of possibilities and examples.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, AppSettings};
/// App::new("myprog")
/// .unset_setting(AppSettings::ColorAuto)
/// # ;
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
/// [`AppSettings`]: ./enum.AppSettings.html
pub fn unset_setting(mut self, setting: AppSettings) -> Self {
self.p.unset(setting);
self
}
/// Disables multiple command, or [`SubCommand`], level settings.
///
/// See [`AppSettings`] for a full list of possibilities and examples.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, AppSettings};
/// App::new("myprog")
/// .unset_settings(&[AppSettings::ColorAuto,
/// AppSettings::AllowInvalidUtf8])
/// # ;
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
/// [`AppSettings`]: ./enum.AppSettings.html
pub fn unset_settings(mut self, settings: &[AppSettings]) -> Self {
for s in settings {
self.p.unset(*s);
}
self
}
/// Sets the terminal width at which to wrap help messages. Defaults to `120`. Using `0` will
/// ignore terminal widths and use source formatting.
///
/// `clap` automatically tries to determine the terminal width on Unix, Linux, macOS and Windows
/// if the `wrap_help` cargo "feature" has been used while compiling. If the terminal width
/// cannot be determined, `clap` defaults to `120`.
///
/// **NOTE:** This setting applies globally and *not* on a per-command basis.
///
/// **NOTE:** This setting must be set **before** any subcommands are added!
///
/// # Platform Specific
///
/// Only Unix, Linux, macOS and Windows support automatic determination of terminal width.
/// Even on those platforms, this setting is useful if for any reason the terminal width
/// cannot be determined.
///
/// # Examples
///
/// ```no_run
/// # use clap::App;
/// App::new("myprog")
/// .set_term_width(80)
/// # ;
/// ```
pub fn set_term_width(mut self, width: usize) -> Self {
self.p.meta.term_w = Some(width);
self
}
/// Sets the max terminal width at which to wrap help messages. Using `0` will ignore terminal
/// widths and use source formatting.
///
/// `clap` automatically tries to determine the terminal width on Unix, Linux, macOS and Windows
/// if the `wrap_help` cargo "feature" has been used while compiling, but one might want to
/// limit the size (e.g. when the terminal is running fullscreen).
///
/// **NOTE:** This setting applies globally and *not* on a per-command basis.
///
/// **NOTE:** This setting must be set **before** any subcommands are added!
///
/// # Platform Specific
///
/// Only Unix, Linux, macOS and Windows support automatic determination of terminal width.
///
/// # Examples
///
/// ```no_run
/// # use clap::App;
/// App::new("myprog")
/// .max_term_width(100)
/// # ;
/// ```
pub fn max_term_width(mut self, w: usize) -> Self {
self.p.meta.max_w = Some(w);
self
}
/// Adds an [argument] to the list of valid possibilities.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// // Adding a single "flag" argument with a short and help text, using Arg::with_name()
/// .arg(
/// Arg::with_name("debug")
/// .short("d")
/// .help("turns on debugging mode")
/// )
/// // Adding a single "option" argument with a short, a long, and help text using the less
/// // verbose Arg::from_usage()
/// .arg(
/// Arg::from_usage("-c --config=[CONFIG] 'Optionally sets a config file to use'")
/// )
/// # ;
/// ```
/// [argument]: ./struct.Arg.html
pub fn arg<A: Into<Arg<'a, 'b>>>(mut self, a: A) -> Self {
self.p.add_arg(a.into());
self
}
/// Adds multiple [arguments] to the list of valid possibilities
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .args(
/// &[Arg::from_usage("[debug] -d 'turns on debugging info'"),
/// Arg::with_name("input").index(1).help("the input file to use")]
/// )
/// # ;
/// ```
/// [arguments]: ./struct.Arg.html
pub fn args(mut self, args: &[Arg<'a, 'b>]) -> Self {
for arg in args {
self.p.add_arg_ref(arg);
}
self
}
/// A convenience method for adding a single [argument] from a usage type string. The string
/// used follows the same rules and syntax as [`Arg::from_usage`]
///
/// **NOTE:** The downside to using this method is that you can not set any additional
/// properties of the [`Arg`] other than what [`Arg::from_usage`] supports.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .arg_from_usage("-c --config=<FILE> 'Sets a configuration file to use'")
/// # ;
/// ```
/// [argument]: ./struct.Arg.html
/// [`Arg`]: ./struct.Arg.html
/// [`Arg::from_usage`]: ./struct.Arg.html#method.from_usage
pub fn arg_from_usage(mut self, usage: &'a str) -> Self {
self.p.add_arg(Arg::from_usage(usage));
self
}
/// Adds multiple [arguments] at once from a usage string, one per line. See
/// [`Arg::from_usage`] for details on the syntax and rules supported.
///
/// **NOTE:** Like [`App::arg_from_usage`] the downside is you only set properties for the
/// [`Arg`]s which [`Arg::from_usage`] supports.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// App::new("myprog")
/// .args_from_usage(
/// "-c --config=[FILE] 'Sets a configuration file to use'
/// [debug]... -d 'Sets the debugging level'
/// <FILE> 'The input file to use'"
/// )
/// # ;
/// ```
/// [arguments]: ./struct.Arg.html
/// [`Arg::from_usage`]: ./struct.Arg.html#method.from_usage
/// [`App::arg_from_usage`]: ./struct.App.html#method.arg_from_usage
/// [`Arg`]: ./struct.Arg.html
pub fn args_from_usage(mut self, usage: &'a str) -> Self {
for line in usage.lines() {
let l = line.trim();
if l.is_empty() {
continue;
}
self.p.add_arg(Arg::from_usage(l));
}
self
}
/// Allows adding a [`SubCommand`] alias, which function as "hidden" subcommands that
/// automatically dispatch as if this subcommand was used. This is more efficient, and easier
/// than creating multiple hidden subcommands as one only needs to check for the existence of
/// this command, and not all variants.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg, SubCommand};
/// let m = App::new("myprog")
/// .subcommand(SubCommand::with_name("test")
/// .alias("do-stuff"))
/// .get_matches_from(vec!["myprog", "do-stuff"]);
/// assert_eq!(m.subcommand_name(), Some("test"));
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
pub fn alias<S: Into<&'b str>>(mut self, name: S) -> Self {
if let Some(ref mut als) = self.p.meta.aliases {
als.push((name.into(), false));
} else {
self.p.meta.aliases = Some(vec![(name.into(), false)]);
}
self
}
/// Allows adding [`SubCommand`] aliases, which function as "hidden" subcommands that
/// automatically dispatch as if this subcommand was used. This is more efficient, and easier
/// than creating multiple hidden subcommands as one only needs to check for the existence of
/// this command, and not all variants.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg, SubCommand};
/// let m = App::new("myprog")
/// .subcommand(SubCommand::with_name("test")
/// .aliases(&["do-stuff", "do-tests", "tests"]))
/// .arg(Arg::with_name("input")
/// .help("the file to add")
/// .index(1)
/// .required(false))
/// .get_matches_from(vec!["myprog", "do-tests"]);
/// assert_eq!(m.subcommand_name(), Some("test"));
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
pub fn aliases(mut self, names: &[&'b str]) -> Self {
if let Some(ref mut als) = self.p.meta.aliases {
for n in names {
als.push((n, false));
}
} else {
self.p.meta.aliases = Some(names.iter().map(|n| (*n, false)).collect::<Vec<_>>());
}
self
}
/// Allows adding a [`SubCommand`] alias that functions exactly like those defined with
/// [`App::alias`], except that they are visible inside the help message.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg, SubCommand};
/// let m = App::new("myprog")
/// .subcommand(SubCommand::with_name("test")
/// .visible_alias("do-stuff"))
/// .get_matches_from(vec!["myprog", "do-stuff"]);
/// assert_eq!(m.subcommand_name(), Some("test"));
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
/// [`App::alias`]: ./struct.App.html#method.alias
pub fn visible_alias<S: Into<&'b str>>(mut self, name: S) -> Self {
if let Some(ref mut als) = self.p.meta.aliases {
als.push((name.into(), true));
} else {
self.p.meta.aliases = Some(vec![(name.into(), true)]);
}
self
}
/// Allows adding multiple [`SubCommand`] aliases that functions exactly like those defined
/// with [`App::aliases`], except that they are visible inside the help message.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg, SubCommand};
/// let m = App::new("myprog")
/// .subcommand(SubCommand::with_name("test")
/// .visible_aliases(&["do-stuff", "tests"]))
/// .get_matches_from(vec!["myprog", "do-stuff"]);
/// assert_eq!(m.subcommand_name(), Some("test"));
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
/// [`App::aliases`]: ./struct.App.html#method.aliases
pub fn visible_aliases(mut self, names: &[&'b str]) -> Self {
if let Some(ref mut als) = self.p.meta.aliases {
for n in names {
als.push((n, true));
}
} else {
self.p.meta.aliases = Some(names.iter().map(|n| (*n, true)).collect::<Vec<_>>());
}
self
}
/// Adds an [`ArgGroup`] to the application. [`ArgGroup`]s are a family of related arguments.
/// By placing them in a logical group, you can build easier requirement and exclusion rules.
/// For instance, you can make an entire [`ArgGroup`] required, meaning that one (and *only*
/// one) argument from that group must be present at runtime.
///
/// You can also do things such as name an [`ArgGroup`] as a conflict to another argument.
/// Meaning any of the arguments that belong to that group will cause a failure if present with
/// the conflicting argument.
///
/// Another added benefit of [`ArgGroup`]s is that you can extract a value from a group instead
/// of determining exactly which argument was used.
///
/// Finally, using [`ArgGroup`]s to ensure exclusion between arguments is another very common
/// use
///
/// # Examples
///
/// The following example demonstrates using an [`ArgGroup`] to ensure that one, and only one,
/// of the arguments from the specified group is present at runtime.
///
/// ```no_run
/// # use clap::{App, ArgGroup};
/// App::new("app")
/// .args_from_usage(
/// "--set-ver [ver] 'set the version manually'
/// --major 'auto increase major'
/// --minor 'auto increase minor'
/// --patch 'auto increase patch'")
/// .group(ArgGroup::with_name("vers")
/// .args(&["set-ver", "major", "minor","patch"])
/// .required(true))
/// # ;
/// ```
/// [`ArgGroup`]: ./struct.ArgGroup.html
pub fn group(mut self, group: ArgGroup<'a>) -> Self {
self.p.add_group(group);
self
}
/// Adds multiple [`ArgGroup`]s to the [`App`] at once.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, ArgGroup};
/// App::new("app")
/// .args_from_usage(
/// "--set-ver [ver] 'set the version manually'
/// --major 'auto increase major'
/// --minor 'auto increase minor'
/// --patch 'auto increase patch'
/// -c [FILE] 'a config file'
/// -i [IFACE] 'an interface'")
/// .groups(&[
/// ArgGroup::with_name("vers")
/// .args(&["set-ver", "major", "minor","patch"])
/// .required(true),
/// ArgGroup::with_name("input")
/// .args(&["c", "i"])
/// ])
/// # ;
/// ```
/// [`ArgGroup`]: ./struct.ArgGroup.html
/// [`App`]: ./struct.App.html
pub fn groups(mut self, groups: &[ArgGroup<'a>]) -> Self {
for g in groups {
self = self.group(g.into());
}
self
}
/// Adds a [`SubCommand`] to the list of valid possibilities. Subcommands are effectively
/// sub-[`App`]s, because they can contain their own arguments, subcommands, version, usage,
/// etc. They also function just like [`App`]s, in that they get their own auto generated help,
/// version, and usage.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg, SubCommand};
/// App::new("myprog")
/// .subcommand(SubCommand::with_name("config")
/// .about("Controls configuration features")
/// .arg_from_usage("<config> 'Required configuration file to use'"))
/// # ;
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
/// [`App`]: ./struct.App.html
pub fn subcommand(mut self, subcmd: App<'a, 'b>) -> Self {
self.p.add_subcommand(subcmd);
self
}
/// Adds multiple subcommands to the list of valid possibilities by iterating over an
/// [`IntoIterator`] of [`SubCommand`]s
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg, SubCommand};
/// # App::new("myprog")
/// .subcommands( vec![
/// SubCommand::with_name("config").about("Controls configuration functionality")
/// .arg(Arg::with_name("config_file").index(1)),
/// SubCommand::with_name("debug").about("Controls debug functionality")])
/// # ;
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
/// [`IntoIterator`]: https://doc.rust-lang.org/std/iter/trait.IntoIterator.html
pub fn subcommands<I>(mut self, subcmds: I) -> Self
where
I: IntoIterator<Item = App<'a, 'b>>,
{
for subcmd in subcmds {
self.p.add_subcommand(subcmd);
}
self
}
/// Allows custom ordering of [`SubCommand`]s within the help message. Subcommands with a lower
/// value will be displayed first in the help message. This is helpful when one would like to
/// emphasise frequently used subcommands, or prioritize those towards the top of the list.
/// Duplicate values **are** allowed. Subcommands with duplicate display orders will be
/// displayed in alphabetical order.
///
/// **NOTE:** The default is 999 for all subcommands.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, SubCommand};
/// let m = App::new("cust-ord")
/// .subcommand(SubCommand::with_name("alpha") // typically subcommands are grouped
/// // alphabetically by name. Subcommands
/// // without a display_order have a value of
/// // 999 and are displayed alphabetically with
/// // all other 999 subcommands
/// .about("Some help and text"))
/// .subcommand(SubCommand::with_name("beta")
/// .display_order(1) // In order to force this subcommand to appear *first*
/// // all we have to do is give it a value lower than 999.
/// // Any other subcommands with a value of 1 will be displayed
/// // alphabetically with this one...then 2 values, then 3, etc.
/// .about("I should be first!"))
/// .get_matches_from(vec![
/// "cust-ord", "--help"
/// ]);
/// ```
///
/// The above example displays the following help message
///
/// ```text
/// cust-ord
///
/// USAGE:
/// cust-ord [FLAGS] [OPTIONS]
///
/// FLAGS:
/// -h, --help Prints help information
/// -V, --version Prints version information
///
/// SUBCOMMANDS:
/// beta I should be first!
/// alpha Some help and text
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
pub fn display_order(mut self, ord: usize) -> Self {
self.p.meta.disp_ord = ord;
self
}
/// Prints the full help message to [`io::stdout()`] using a [`BufWriter`] using the same
/// method as if someone ran `-h` to request the help message
///
/// **NOTE:** clap has the ability to distinguish between "short" and "long" help messages
/// depending on if the user ran [`-h` (short)] or [`--help` (long)]
///
/// # Examples
///
/// ```rust
/// # use clap::App;
/// let mut app = App::new("myprog");
/// app.print_help();
/// ```
/// [`io::stdout()`]: https://doc.rust-lang.org/std/io/fn.stdout.html
/// [`BufWriter`]: https://doc.rust-lang.org/std/io/struct.BufWriter.html
/// [`-h` (short)]: ./struct.Arg.html#method.help
/// [`--help` (long)]: ./struct.Arg.html#method.long_help
pub fn print_help(&mut self) -> ClapResult<()> {
// If there are global arguments, or settings we need to propagate them down to subcommands
// before parsing incase we run into a subcommand
self.p.propagate_globals();
self.p.propagate_settings();
self.p.derive_display_order();
self.p.create_help_and_version();
let out = io::stdout();
let mut buf_w = BufWriter::new(out.lock());
self.write_help(&mut buf_w)
}
/// Prints the full help message to [`io::stdout()`] using a [`BufWriter`] using the same
/// method as if someone ran `--help` to request the help message
///
/// **NOTE:** clap has the ability to distinguish between "short" and "long" help messages
/// depending on if the user ran [`-h` (short)] or [`--help` (long)]
///
/// # Examples
///
/// ```rust
/// # use clap::App;
/// let mut app = App::new("myprog");
/// app.print_long_help();
/// ```
/// [`io::stdout()`]: https://doc.rust-lang.org/std/io/fn.stdout.html
/// [`BufWriter`]: https://doc.rust-lang.org/std/io/struct.BufWriter.html
/// [`-h` (short)]: ./struct.Arg.html#method.help
/// [`--help` (long)]: ./struct.Arg.html#method.long_help
pub fn print_long_help(&mut self) -> ClapResult<()> {
let out = io::stdout();
let mut buf_w = BufWriter::new(out.lock());
self.write_long_help(&mut buf_w)
}
/// Writes the full help message to the user to a [`io::Write`] object in the same method as if
/// the user ran `-h`
///
/// **NOTE:** clap has the ability to distinguish between "short" and "long" help messages
/// depending on if the user ran [`-h` (short)] or [`--help` (long)]
///
/// **NOTE:** There is a known bug where this method does not write propagated global arguments
/// or autogenerated arguments (i.e. the default help/version args). Prefer
/// [`App::write_long_help`] instead if possible!
///
/// # Examples
///
/// ```rust
/// # use clap::App;
/// use std::io;
/// let mut app = App::new("myprog");
/// let mut out = io::stdout();
/// app.write_help(&mut out).expect("failed to write to stdout");
/// ```
/// [`io::Write`]: https://doc.rust-lang.org/std/io/trait.Write.html
/// [`-h` (short)]: ./struct.Arg.html#method.help
/// [`--help` (long)]: ./struct.Arg.html#method.long_help
pub fn write_help<W: Write>(&self, w: &mut W) -> ClapResult<()> {
// PENDING ISSUE: 808
// https://github.com/clap-rs/clap/issues/808
// If there are global arguments, or settings we need to propagate them down to subcommands
// before parsing incase we run into a subcommand
// self.p.propagate_globals();
// self.p.propagate_settings();
// self.p.derive_display_order();
// self.p.create_help_and_version();
Help::write_app_help(w, self, false)
}
/// Writes the full help message to the user to a [`io::Write`] object in the same method as if
/// the user ran `--help`
///
/// **NOTE:** clap has the ability to distinguish between "short" and "long" help messages
/// depending on if the user ran [`-h` (short)] or [`--help` (long)]
///
/// # Examples
///
/// ```rust
/// # use clap::App;
/// use std::io;
/// let mut app = App::new("myprog");
/// let mut out = io::stdout();
/// app.write_long_help(&mut out).expect("failed to write to stdout");
/// ```
/// [`io::Write`]: https://doc.rust-lang.org/std/io/trait.Write.html
/// [`-h` (short)]: ./struct.Arg.html#method.help
/// [`--help` (long)]: ./struct.Arg.html#method.long_help
pub fn write_long_help<W: Write>(&mut self, w: &mut W) -> ClapResult<()> {
// If there are global arguments, or settings we need to propagate them down to subcommands
// before parsing incase we run into a subcommand
self.p.propagate_globals();
self.p.propagate_settings();
self.p.derive_display_order();
self.p.create_help_and_version();
Help::write_app_help(w, self, true)
}
/// Writes the version message to the user to a [`io::Write`] object as if the user ran `-V`.
///
/// **NOTE:** clap has the ability to distinguish between "short" and "long" version messages
/// depending on if the user ran [`-V` (short)] or [`--version` (long)]
///
/// # Examples
///
/// ```rust
/// # use clap::App;
/// use std::io;
/// let mut app = App::new("myprog");
/// let mut out = io::stdout();
/// app.write_version(&mut out).expect("failed to write to stdout");
/// ```
/// [`io::Write`]: https://doc.rust-lang.org/std/io/trait.Write.html
/// [`-V` (short)]: ./struct.App.html#method.version
/// [`--version` (long)]: ./struct.App.html#method.long_version
pub fn write_version<W: Write>(&self, w: &mut W) -> ClapResult<()> {
self.p.write_version(w, false).map_err(From::from)
}
/// Writes the version message to the user to a [`io::Write`] object
///
/// **NOTE:** clap has the ability to distinguish between "short" and "long" version messages
/// depending on if the user ran [`-V` (short)] or [`--version` (long)]
///
/// # Examples
///
/// ```rust
/// # use clap::App;
/// use std::io;
/// let mut app = App::new("myprog");
/// let mut out = io::stdout();
/// app.write_long_version(&mut out).expect("failed to write to stdout");
/// ```
/// [`io::Write`]: https://doc.rust-lang.org/std/io/trait.Write.html
/// [`-V` (short)]: ./struct.App.html#method.version
/// [`--version` (long)]: ./struct.App.html#method.long_version
pub fn write_long_version<W: Write>(&self, w: &mut W) -> ClapResult<()> {
self.p.write_version(w, true).map_err(From::from)
}
/// Generate a completions file for a specified shell at compile time.
///
/// **NOTE:** to generate the file at compile time you must use a `build.rs` "Build Script"
///
/// # Examples
///
/// The following example generates a bash completion script via a `build.rs` script. In this
/// simple example, we'll demo a very small application with only a single subcommand and two
/// args. Real applications could be many multiple levels deep in subcommands, and have tens or
/// potentially hundreds of arguments.
///
/// First, it helps if we separate out our `App` definition into a separate file. Whether you
/// do this as a function, or bare App definition is a matter of personal preference.
///
/// ```
/// // src/cli.rs
///
/// use clap::{App, Arg, SubCommand};
///
/// pub fn build_cli() -> App<'static, 'static> {
/// App::new("compl")
/// .about("Tests completions")
/// .arg(Arg::with_name("file")
/// .help("some input file"))
/// .subcommand(SubCommand::with_name("test")
/// .about("tests things")
/// .arg(Arg::with_name("case")
/// .long("case")
/// .takes_value(true)
/// .help("the case to test")))
/// }
/// ```
///
/// In our regular code, we can simply call this `build_cli()` function, then call
/// `get_matches()`, or any of the other normal methods directly after. For example:
///
/// ```ignore
/// // src/main.rs
///
/// mod cli;
///
/// fn main() {
/// let m = cli::build_cli().get_matches();
///
/// // normal logic continues...
/// }
/// ```
///
/// Next, we set up our `Cargo.toml` to use a `build.rs` build script.
///
/// ```toml
/// # Cargo.toml
/// build = "build.rs"
///
/// [build-dependencies]
/// clap = "2.23"
/// ```
///
/// Next, we place a `build.rs` in our project root.
///
/// ```ignore
/// extern crate clap;
///
/// use clap::Shell;
///
/// include!("src/cli.rs");
///
/// fn main() {
/// let outdir = match env::var_os("OUT_DIR") {
/// None => return,
/// Some(outdir) => outdir,
/// };
/// let mut app = build_cli();
/// app.gen_completions("myapp", // We need to specify the bin name manually
/// Shell::Bash, // Then say which shell to build completions for
/// outdir); // Then say where write the completions to
/// }
/// ```
/// Now, once we compile there will be a `{bin_name}.bash` file in the directory.
/// Assuming we compiled with debug mode, it would be somewhere similar to
/// `<project>/target/debug/build/myapp-<hash>/out/myapp.bash`.
///
/// Fish shell completions will use the file format `{bin_name}.fish`
pub fn gen_completions<T: Into<OsString>, S: Into<String>>(
&mut self,
bin_name: S,
for_shell: Shell,
out_dir: T,
) {
self.p.meta.bin_name = Some(bin_name.into());
self.p.gen_completions(for_shell, out_dir.into());
}
/// Generate a completions file for a specified shell at runtime. Until `cargo install` can
/// install extra files like a completion script, this may be used e.g. in a command that
/// outputs the contents of the completion script, to be redirected into a file by the user.
///
/// # Examples
///
/// Assuming a separate `cli.rs` like the [example above](./struct.App.html#method.gen_completions),
/// we can let users generate a completion script using a command:
///
/// ```ignore
/// // src/main.rs
///
/// mod cli;
/// use std::io;
///
/// fn main() {
/// let matches = cli::build_cli().get_matches();
///
/// if matches.is_present("generate-bash-completions") {
/// cli::build_cli().gen_completions_to("myapp", Shell::Bash, &mut io::stdout());
/// }
///
/// // normal logic continues...
/// }
///
/// ```
///
/// Usage:
///
/// ```shell
/// $ myapp generate-bash-completions > /usr/share/bash-completion/completions/myapp.bash
/// ```
pub fn gen_completions_to<W: Write, S: Into<String>>(
&mut self,
bin_name: S,
for_shell: Shell,
buf: &mut W,
) {
self.p.meta.bin_name = Some(bin_name.into());
self.p.gen_completions_to(for_shell, buf);
}
/// Starts the parsing process, upon a failed parse an error will be displayed to the user and
/// the process will exit with the appropriate error code. By default this method gets all user
/// provided arguments from [`env::args_os`] in order to allow for invalid UTF-8 code points,
/// which are legal on many platforms.
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// let matches = App::new("myprog")
/// // Args and options go here...
/// .get_matches();
/// ```
/// [`env::args_os`]: https://doc.rust-lang.org/std/env/fn.args_os.html
pub fn get_matches(self) -> ArgMatches<'a> {
self.get_matches_from(&mut env::args_os())
}
/// Starts the parsing process. This method will return a [`clap::Result`] type instead of exiting
/// the process on failed parse. By default this method gets matches from [`env::args_os`]
///
/// **NOTE:** This method WILL NOT exit when `--help` or `--version` (or short versions) are
/// used. It will return a [`clap::Error`], where the [`kind`] is a
/// [`ErrorKind::HelpDisplayed`] or [`ErrorKind::VersionDisplayed`] respectively. You must call
/// [`Error::exit`] or perform a [`std::process::exit`].
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// let matches = App::new("myprog")
/// // Args and options go here...
/// .get_matches_safe()
/// .unwrap_or_else( |e| e.exit() );
/// ```
/// [`env::args_os`]: https://doc.rust-lang.org/std/env/fn.args_os.html
/// [`ErrorKind::HelpDisplayed`]: ./enum.ErrorKind.html#variant.HelpDisplayed
/// [`ErrorKind::VersionDisplayed`]: ./enum.ErrorKind.html#variant.VersionDisplayed
/// [`Error::exit`]: ./struct.Error.html#method.exit
/// [`std::process::exit`]: https://doc.rust-lang.org/std/process/fn.exit.html
/// [`clap::Result`]: ./type.Result.html
/// [`clap::Error`]: ./struct.Error.html
/// [`kind`]: ./struct.Error.html
pub fn get_matches_safe(self) -> ClapResult<ArgMatches<'a>> {
// Start the parsing
self.get_matches_from_safe(&mut env::args_os())
}
/// Starts the parsing process. Like [`App::get_matches`] this method does not return a [`clap::Result`]
/// and will automatically exit with an error message. This method, however, lets you specify
/// what iterator to use when performing matches, such as a [`Vec`] of your making.
///
/// **NOTE:** The first argument will be parsed as the binary name unless
/// [`AppSettings::NoBinaryName`] is used
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// let arg_vec = vec!["my_prog", "some", "args", "to", "parse"];
///
/// let matches = App::new("myprog")
/// // Args and options go here...
/// .get_matches_from(arg_vec);
/// ```
/// [`App::get_matches`]: ./struct.App.html#method.get_matches
/// [`clap::Result`]: ./type.Result.html
/// [`Vec`]: https://doc.rust-lang.org/std/vec/struct.Vec.html
/// [`AppSettings::NoBinaryName`]: ./enum.AppSettings.html#variant.NoBinaryName
pub fn get_matches_from<I, T>(mut self, itr: I) -> ArgMatches<'a>
where
I: IntoIterator<Item = T>,
T: Into<OsString> + Clone,
{
self.get_matches_from_safe_borrow(itr).unwrap_or_else(|e| {
// Otherwise, write to stderr and exit
if e.use_stderr() {
wlnerr!("{}", e.message);
if self.p.is_set(AppSettings::WaitOnError) {
wlnerr!("\nPress [ENTER] / [RETURN] to continue...");
let mut s = String::new();
let i = io::stdin();
i.lock().read_line(&mut s).unwrap();
}
drop(self);
drop(e);
process::exit(1);
}
drop(self);
e.exit()
})
}
/// Starts the parsing process. A combination of [`App::get_matches_from`], and
/// [`App::get_matches_safe`]
///
/// **NOTE:** This method WILL NOT exit when `--help` or `--version` (or short versions) are
/// used. It will return a [`clap::Error`], where the [`kind`] is a [`ErrorKind::HelpDisplayed`]
/// or [`ErrorKind::VersionDisplayed`] respectively. You must call [`Error::exit`] or
/// perform a [`std::process::exit`] yourself.
///
/// **NOTE:** The first argument will be parsed as the binary name unless
/// [`AppSettings::NoBinaryName`] is used
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// let arg_vec = vec!["my_prog", "some", "args", "to", "parse"];
///
/// let matches = App::new("myprog")
/// // Args and options go here...
/// .get_matches_from_safe(arg_vec)
/// .unwrap_or_else( |e| { panic!("An error occurs: {}", e) });
/// ```
/// [`App::get_matches_from`]: ./struct.App.html#method.get_matches_from
/// [`App::get_matches_safe`]: ./struct.App.html#method.get_matches_safe
/// [`ErrorKind::HelpDisplayed`]: ./enum.ErrorKind.html#variant.HelpDisplayed
/// [`ErrorKind::VersionDisplayed`]: ./enum.ErrorKind.html#variant.VersionDisplayed
/// [`Error::exit`]: ./struct.Error.html#method.exit
/// [`std::process::exit`]: https://doc.rust-lang.org/std/process/fn.exit.html
/// [`clap::Error`]: ./struct.Error.html
/// [`Error::exit`]: ./struct.Error.html#method.exit
/// [`kind`]: ./struct.Error.html
/// [`AppSettings::NoBinaryName`]: ./enum.AppSettings.html#variant.NoBinaryName
pub fn get_matches_from_safe<I, T>(mut self, itr: I) -> ClapResult<ArgMatches<'a>>
where
I: IntoIterator<Item = T>,
T: Into<OsString> + Clone,
{
self.get_matches_from_safe_borrow(itr)
}
/// Starts the parsing process without consuming the [`App`] struct `self`. This is normally not
/// the desired functionality, instead prefer [`App::get_matches_from_safe`] which *does*
/// consume `self`.
///
/// **NOTE:** The first argument will be parsed as the binary name unless
/// [`AppSettings::NoBinaryName`] is used
///
/// # Examples
///
/// ```no_run
/// # use clap::{App, Arg};
/// let arg_vec = vec!["my_prog", "some", "args", "to", "parse"];
///
/// let mut app = App::new("myprog");
/// // Args and options go here...
/// let matches = app.get_matches_from_safe_borrow(arg_vec)
/// .unwrap_or_else( |e| { panic!("An error occurs: {}", e) });
/// ```
/// [`App`]: ./struct.App.html
/// [`App::get_matches_from_safe`]: ./struct.App.html#method.get_matches_from_safe
/// [`AppSettings::NoBinaryName`]: ./enum.AppSettings.html#variant.NoBinaryName
pub fn get_matches_from_safe_borrow<I, T>(&mut self, itr: I) -> ClapResult<ArgMatches<'a>>
where
I: IntoIterator<Item = T>,
T: Into<OsString> + Clone,
{
// If there are global arguments, or settings we need to propagate them down to subcommands
// before parsing incase we run into a subcommand
if !self.p.is_set(AppSettings::Propagated) {
self.p.propagate_globals();
self.p.propagate_settings();
self.p.derive_display_order();
self.p.set(AppSettings::Propagated);
}
let mut matcher = ArgMatcher::new();
let mut it = itr.into_iter();
// Get the name of the program (argument 1 of env::args()) and determine the
// actual file
// that was used to execute the program. This is because a program called
// ./target/release/my_prog -a
// will have two arguments, './target/release/my_prog', '-a' but we don't want
// to display
// the full path when displaying help messages and such
if !self.p.is_set(AppSettings::NoBinaryName) {
if let Some(name) = it.next() {
let bn_os = name.into();
let p = Path::new(&*bn_os);
if let Some(f) = p.file_name() {
if let Some(s) = f.to_os_string().to_str() {
if self.p.meta.bin_name.is_none() {
self.p.meta.bin_name = Some(s.to_owned());
}
}
}
}
}
// do the real parsing
if let Err(e) = self.p.get_matches_with(&mut matcher, &mut it.peekable()) {
return Err(e);
}
let global_arg_vec: Vec<&str> = self.p.global_args.iter().map(|ga| ga.b.name).collect();
matcher.propagate_globals(&global_arg_vec);
Ok(matcher.into())
}
}
#[cfg(feature = "yaml")]
impl<'a> From<&'a Yaml> for App<'a, 'a> {
fn from(mut yaml: &'a Yaml) -> Self {
use crate::args::SubCommand;
// We WANT this to panic on error...so expect() is good.
let mut is_sc = None;
let mut a = if let Some(name) = yaml["name"].as_str() {
App::new(name)
} else {
let yaml_hash = yaml.as_hash().unwrap();
let sc_key = yaml_hash.keys().nth(0).unwrap();
is_sc = Some(yaml_hash.get(sc_key).unwrap());
App::new(sc_key.as_str().unwrap())
};
yaml = if let Some(sc) = is_sc { sc } else { yaml };
macro_rules! yaml_str {
($a:ident, $y:ident, $i:ident) => {
if let Some(v) = $y[stringify!($i)].as_str() {
$a = $a.$i(v);
} else if $y[stringify!($i)] != Yaml::BadValue {
panic!(
"Failed to convert YAML value {:?} to a string",
$y[stringify!($i)]
);
}
};
}
yaml_str!(a, yaml, version);
yaml_str!(a, yaml, long_version);
yaml_str!(a, yaml, author);
yaml_str!(a, yaml, bin_name);
yaml_str!(a, yaml, about);
yaml_str!(a, yaml, long_about);
yaml_str!(a, yaml, before_help);
yaml_str!(a, yaml, after_help);
yaml_str!(a, yaml, template);
yaml_str!(a, yaml, usage);
yaml_str!(a, yaml, help);
yaml_str!(a, yaml, help_short);
yaml_str!(a, yaml, version_short);
yaml_str!(a, yaml, help_message);
yaml_str!(a, yaml, version_message);
yaml_str!(a, yaml, alias);
yaml_str!(a, yaml, visible_alias);
if let Some(v) = yaml["display_order"].as_i64() {
a = a.display_order(v as usize);
} else if yaml["display_order"] != Yaml::BadValue {
panic!(
"Failed to convert YAML value {:?} to a u64",
yaml["display_order"]
);
}
if let Some(v) = yaml["setting"].as_str() {
a = a.setting(v.parse().expect("unknown AppSetting found in YAML file"));
} else if yaml["setting"] != Yaml::BadValue {
panic!(
"Failed to convert YAML value {:?} to an AppSetting",
yaml["setting"]
);
}
if let Some(v) = yaml["settings"].as_vec() {
for ys in v {
if let Some(s) = ys.as_str() {
a = a.setting(s.parse().expect("unknown AppSetting found in YAML file"));
}
}
} else if let Some(v) = yaml["settings"].as_str() {
a = a.setting(v.parse().expect("unknown AppSetting found in YAML file"));
} else if yaml["settings"] != Yaml::BadValue {
panic!(
"Failed to convert YAML value {:?} to a string",
yaml["settings"]
);
}
if let Some(v) = yaml["global_setting"].as_str() {
a = a.setting(v.parse().expect("unknown AppSetting found in YAML file"));
} else if yaml["global_setting"] != Yaml::BadValue {
panic!(
"Failed to convert YAML value {:?} to an AppSetting",
yaml["setting"]
);
}
if let Some(v) = yaml["global_settings"].as_vec() {
for ys in v {
if let Some(s) = ys.as_str() {
a = a.global_setting(s.parse().expect("unknown AppSetting found in YAML file"));
}
}
} else if let Some(v) = yaml["global_settings"].as_str() {
a = a.global_setting(v.parse().expect("unknown AppSetting found in YAML file"));
} else if yaml["global_settings"] != Yaml::BadValue {
panic!(
"Failed to convert YAML value {:?} to a string",
yaml["global_settings"]
);
}
macro_rules! vec_or_str {
($a:ident, $y:ident, $as_vec:ident, $as_single:ident) => {{
let maybe_vec = $y[stringify!($as_vec)].as_vec();
if let Some(vec) = maybe_vec {
for ys in vec {
if let Some(s) = ys.as_str() {
$a = $a.$as_single(s);
} else {
panic!("Failed to convert YAML value {:?} to a string", ys);
}
}
} else {
if let Some(s) = $y[stringify!($as_vec)].as_str() {
$a = $a.$as_single(s);
} else if $y[stringify!($as_vec)] != Yaml::BadValue {
panic!(
"Failed to convert YAML value {:?} to either a vec or string",
$y[stringify!($as_vec)]
);
}
}
$a
}};
}
a = vec_or_str!(a, yaml, aliases, alias);
a = vec_or_str!(a, yaml, visible_aliases, visible_alias);
if let Some(v) = yaml["args"].as_vec() {
for arg_yaml in v {
a = a.arg(Arg::from_yaml(arg_yaml.as_hash().unwrap()));
}
}
if let Some(v) = yaml["subcommands"].as_vec() {
for sc_yaml in v {
a = a.subcommand(SubCommand::from_yaml(sc_yaml));
}
}
if let Some(v) = yaml["groups"].as_vec() {
for ag_yaml in v {
a = a.group(ArgGroup::from(ag_yaml.as_hash().unwrap()));
}
}
a
}
}
impl<'a, 'b> Clone for App<'a, 'b> {
fn clone(&self) -> Self {
App { p: self.p.clone() }
}
}
impl<'n, 'e> AnyArg<'n, 'e> for App<'n, 'e> {
fn name(&self) -> &'n str {
""
}
fn overrides(&self) -> Option<&[&'e str]> {
None
}
fn requires(&self) -> Option<&[(Option<&'e str>, &'n str)]> {
None
}
fn blacklist(&self) -> Option<&[&'e str]> {
None
}
fn required_unless(&self) -> Option<&[&'e str]> {
None
}
fn val_names(&self) -> Option<&VecMap<&'e str>> {
None
}
fn is_set(&self, _: ArgSettings) -> bool {
false
}
fn val_terminator(&self) -> Option<&'e str> {
None
}
fn set(&mut self, _: ArgSettings) {
unreachable!("App struct does not support AnyArg::set, this is a bug!")
}
fn has_switch(&self) -> bool {
false
}
fn max_vals(&self) -> Option<u64> {
None
}
fn num_vals(&self) -> Option<u64> {
None
}
fn possible_vals(&self) -> Option<&[&'e str]> {
None
}
#[cfg_attr(feature = "cargo-clippy", allow(clippy::type_complexity))]
fn validator(&self) -> Option<&Rc<Fn(String) -> StdResult<(), String>>> {
None
}
#[cfg_attr(feature = "cargo-clippy", allow(clippy::type_complexity))]
fn validator_os(&self) -> Option<&Rc<Fn(&OsStr) -> StdResult<(), OsString>>> {
None
}
fn min_vals(&self) -> Option<u64> {
None
}
fn short(&self) -> Option<char> {
None
}
fn long(&self) -> Option<&'e str> {
None
}
fn val_delim(&self) -> Option<char> {
None
}
fn takes_value(&self) -> bool {
true
}
fn help(&self) -> Option<&'e str> {
self.p.meta.about
}
fn long_help(&self) -> Option<&'e str> {
self.p.meta.long_about
}
fn default_val(&self) -> Option<&'e OsStr> {
None
}
fn default_vals_ifs(&self) -> Option<map::Values<(&'n str, Option<&'e OsStr>, &'e OsStr)>> {
None
}
fn env<'s>(&'s self) -> Option<(&'n OsStr, Option<&'s OsString>)> {
None
}
fn longest_filter(&self) -> bool {
true
}
fn aliases(&self) -> Option<Vec<&'e str>> {
if let Some(ref aliases) = self.p.meta.aliases {
let vis_aliases: Vec<_> = aliases
.iter()
.filter_map(|&(n, v)| if v { Some(n) } else { None })
.collect();
if vis_aliases.is_empty() {
None
} else {
Some(vis_aliases)
}
} else {
None
}
}
}
impl<'n, 'e> fmt::Display for App<'n, 'e> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}", self.p.meta.name)
}
}