      1
      2
      3
      4
      5
      6
      7
      8
      9
     10
     11
     12
     13
     14
     15
     16
     17
     18
     19
     20
     21
     22
     23
     24
     25
     26
     27
     28
     29
     30
     31
     32
     33
     34
     35
     36
     37
     38
     39
     40
     41
     42
     43
     44
     45
     46
     47
     48
     49
     50
     51
     52
     53
     54
     55
     56
     57
     58
     59
     60
     61
     62
     63
     64
     65
     66
     67
     68
     69
     70
     71
     72
     73
     74
     75
     76
     77
     78
     79
     80
     81
     82
     83
     84
     85
     86
     87
     88
     89
     90
     91
     92
     93
     94
     95
     96
     97
     98
     99
    100
    101
    102
    103
    104
    105
    106
    107
    108
    109
    110
    111
    112
    113
    114
    115
    116
    117
    118
    119
    120
    121
    122
    123
    124
    125
    126
    127
    128
    129
    130
    131
    132
    133
    134
    135
    136
    137
    138
    139
    140
    141
    142
    143
    144
    145
    146
    147
    148
    149
    150
    151
    152
    153
    154
    155
    156
    157
    158
    159
    160
    161
    162
    163
    164
    165
    166
    167
    168
    169
    170
    171
    172
    173
    174
    175
    176
    177
    178
    179
    180
    181
    182
    183
    184
    185
    186
    187
    188
    189
    190
    191
    192
    193
    194
    195
    196
    197
    198
    199
    200
    201
    202
    203
    204
    205
    206
    207
    208
    209
    210
    211
    212
    213
    214
    215
    216
    217
    218
    219
    220
    221
    222
    223
    224
    225
    226
    227
    228
    229
    230
    231
    232
    233
    234
    235
    236
    237
    238
    239
    240
    241
    242
    243
    244
    245
    246
    247
    248
    249
    250
    251
    252
    253
    254
    255
    256
    257
    258
    259
    260
    261
    262
    263
    264
    265
    266
    267
    268
    269
    270
    271
    272
    273
    274
    275
    276
    277
    278
    279
    280
    281
    282
    283
    284
    285
    286
    287
    288
    289
    290
    291
    292
    293
    294
    295
    296
    297
    298
    299
    300
    301
    302
    303
    304
    305
    306
    307
    308
    309

    use std::str::FromStr;
    use std::ascii::AsciiExt;

    bitflags! {
        flags Flags: u32 {
            const SC_NEGATE_REQS       = 0b000000000000001,
            const SC_REQUIRED          = 0b000000000000010,
            const A_REQUIRED_ELSE_HELP = 0b000000000000100,
            const GLOBAL_VERSION       = 0b000000000001000,
            const VERSIONLESS_SC       = 0b000000000010000,
            const UNIFIED_HELP         = 0b000000000100000,
            const WAIT_ON_ERROR        = 0b000000001000000,
            const SC_REQUIRED_ELSE_HELP= 0b000000010000000,
            const NEEDS_LONG_HELP      = 0b000000100000000,
            const NEEDS_LONG_VERSION   = 0b000001000000000,
            const NEEDS_SC_HELP        = 0b000010000000000,
            const DISABLE_VERSION      = 0b000100000000000,
            const HIDDEN               = 0b001000000000000,
            const TRAILING_VARARG      = 0b010000000000000,
            const NO_BIN_NAME          = 0b100000000000000,
        }
    }

    #[derive(Debug)]
    pub struct AppFlags(Flags);

    impl AppFlags {
        pub fn new() -> Self {
            AppFlags(NEEDS_LONG_VERSION | NEEDS_LONG_HELP | NEEDS_SC_HELP)
        }

        pub fn set(&mut self, s: &AppSettings) {
            match *s {
                AppSettings::SubcommandsNegateReqs => self.0.insert(SC_NEGATE_REQS),
                AppSettings::VersionlessSubcommands => self.0.insert(VERSIONLESS_SC),
                AppSettings::SubcommandRequired => self.0.insert(SC_REQUIRED),
                AppSettings::ArgRequiredElseHelp => self.0.insert(A_REQUIRED_ELSE_HELP),
                AppSettings::GlobalVersion => self.0.insert(GLOBAL_VERSION),
                AppSettings::UnifiedHelpMessage => self.0.insert(UNIFIED_HELP),
                AppSettings::WaitOnError => self.0.insert(WAIT_ON_ERROR),
                AppSettings::SubcommandRequiredElseHelp => self.0.insert(SC_REQUIRED_ELSE_HELP),
                AppSettings::NeedsLongHelp => self.0.insert(NEEDS_LONG_HELP),
                AppSettings::NeedsLongVersion => self.0.insert(NEEDS_LONG_VERSION),
                AppSettings::NeedsSubcommandHelp => self.0.insert(NEEDS_SC_HELP),
                AppSettings::DisableVersion => self.0.insert(DISABLE_VERSION),
                AppSettings::Hidden => self.0.insert(HIDDEN),
                AppSettings::TrailingVarArg => self.0.insert(TRAILING_VARARG),
                AppSettings::NoBinaryName => self.0.insert(NO_BIN_NAME),
            }
        }

        pub fn unset(&mut self, s: &AppSettings) {
            match *s {
                AppSettings::SubcommandsNegateReqs => self.0.remove(SC_NEGATE_REQS),
                AppSettings::VersionlessSubcommands => self.0.remove(VERSIONLESS_SC),
                AppSettings::SubcommandRequired => self.0.remove(SC_REQUIRED),
                AppSettings::ArgRequiredElseHelp => self.0.remove(A_REQUIRED_ELSE_HELP),
                AppSettings::GlobalVersion => self.0.remove(GLOBAL_VERSION),
                AppSettings::UnifiedHelpMessage => self.0.remove(UNIFIED_HELP),
                AppSettings::WaitOnError => self.0.remove(WAIT_ON_ERROR),
                AppSettings::SubcommandRequiredElseHelp => self.0.remove(SC_REQUIRED_ELSE_HELP),
                AppSettings::NeedsLongHelp => self.0.remove(NEEDS_LONG_HELP),
                AppSettings::NeedsLongVersion => self.0.remove(NEEDS_LONG_VERSION),
                AppSettings::NeedsSubcommandHelp => self.0.remove(NEEDS_SC_HELP),
                AppSettings::DisableVersion => self.0.remove(DISABLE_VERSION),
                AppSettings::Hidden => self.0.remove(HIDDEN),
                AppSettings::TrailingVarArg => self.0.remove(TRAILING_VARARG),
                AppSettings::NoBinaryName => self.0.remove(NO_BIN_NAME),
            }
        }

        pub fn is_set(&self, s: &AppSettings) -> bool {
            match *s {
                AppSettings::SubcommandsNegateReqs => self.0.contains(SC_NEGATE_REQS),
                AppSettings::VersionlessSubcommands => self.0.contains(VERSIONLESS_SC),
                AppSettings::SubcommandRequired => self.0.contains(SC_REQUIRED),
                AppSettings::ArgRequiredElseHelp => self.0.contains(A_REQUIRED_ELSE_HELP),
                AppSettings::GlobalVersion => self.0.contains(GLOBAL_VERSION),
                AppSettings::UnifiedHelpMessage => self.0.contains(UNIFIED_HELP),
                AppSettings::WaitOnError => self.0.contains(WAIT_ON_ERROR),
                AppSettings::SubcommandRequiredElseHelp => self.0.contains(SC_REQUIRED_ELSE_HELP),
                AppSettings::NeedsLongHelp => self.0.contains(NEEDS_LONG_HELP),
                AppSettings::NeedsLongVersion => self.0.contains(NEEDS_LONG_VERSION),
                AppSettings::NeedsSubcommandHelp => self.0.contains(NEEDS_SC_HELP),
                AppSettings::DisableVersion => self.0.contains(DISABLE_VERSION),
                AppSettings::Hidden => self.0.contains(HIDDEN),
                AppSettings::TrailingVarArg => self.0.contains(TRAILING_VARARG),
                AppSettings::NoBinaryName => self.0.contains(NO_BIN_NAME),
            }
        }
    }

    /// Application level settings, which affect how `App` operates
    #[derive(Debug, PartialEq, Copy, Clone)]
    pub enum AppSettings {
        /// Allows subcommands to override all requirements of the parent (this command). For example
        /// if you had a subcommand or even top level application which had a required arguments that
        /// are only required as long as there is no subcommand present.
        ///
        /// **NOTE:** This defaults to false (using subcommand does *not* negate requirements)
        ///
        /// # Examples
        ///
        /// ```no_run
        /// # use clap::{App, AppSettings};
        /// App::new("myprog")
        ///     .setting(AppSettings::SubcommandsNegateReqs)
        /// # ;
        /// ```
        SubcommandsNegateReqs,
        /// Allows specifying that if no subcommand is present at runtime, error and exit gracefully
        ///
        /// **NOTE:** This defaults to false (subcommands do *not* need to be present)
        ///
        /// # Examples
        ///
        /// ```no_run
        /// # use clap::{App, AppSettings};
        /// App::new("myprog")
        ///     .setting(AppSettings::SubcommandRequired)
        /// # ;
        /// ```
        SubcommandRequired,
        /// Specifies that the help text should be displayed (and then exit gracefully), if no
        /// arguments are present at runtime (i.e. an empty run such as, `$ myprog`.
        ///
        /// **NOTE:** Subcommands count as arguments
        ///
        /// # Examples
        ///
        /// ```no_run
        /// # use clap::{App, AppSettings};
        /// App::new("myprog")
        ///     .setting(AppSettings::ArgRequiredElseHelp)
        /// # ;
        /// ```
        ArgRequiredElseHelp,
        /// Uses version of the current command for all subcommands. (Defaults to false; subcommands
        /// have independant version strings)
        ///
        /// **NOTE:** The version for the current command and this setting must be set **prior** to
        /// adding any subcommands
        ///
        /// # Examples
        ///
        /// ```no_run
        /// # use clap::{App, Arg, SubCommand, AppSettings};
        /// App::new("myprog")
        ///     .version("v1.1")
        ///     .setting(AppSettings::GlobalVersion)
        ///     .subcommand(SubCommand::with_name("test"))
        ///     .get_matches();
        /// // running `myprog test --version` will display
        /// // "myprog-test v1.1"
        /// ```
        GlobalVersion,
        /// Disables `-V` and `--version` for all subcommands (Defaults to false; subcommands have
        /// version flags)
        ///
        /// **NOTE:** This setting must be set **prior** adding any subcommands
        ///
        /// **NOTE:** Do not set this value to false, it will have undesired results!
        ///
        /// # Examples
        ///
        /// ```no_run
        /// # use clap::{App, Arg, SubCommand, AppSettings};
        /// App::new("myprog")
        ///     .version("v1.1")
        ///     .setting(AppSettings::VersionlessSubcommands)
        ///     .subcommand(SubCommand::with_name("test"))
        ///     .get_matches();
        /// // running `myprog test --version` will display unknown argument error
        /// ```
        VersionlessSubcommands,
        /// By default the auto-generated help message groups flags, options, and positional arguments
        /// separately. This setting disable that and groups flags and options together presenting a
        /// more unified help message (a la getopts or docopt style).
        ///
        /// **NOTE:** This setting is cosmetic only and does not affect any functionality.
        ///
        /// # Examples
        ///
        /// ```no_run
        /// # use clap::{App, Arg, SubCommand, AppSettings};
        /// App::new("myprog")
        ///     .setting(AppSettings::UnifiedHelpMessage)
        ///     .get_matches();
        /// // running `myprog --help` will display a unified "docopt" or "getopts" style help message
        /// ```
        UnifiedHelpMessage,
        /// Will display a message "Press [ENTER]/[RETURN] to continue..." and wait user before
        /// exiting
        ///
        /// This is most useful when writing an application which is run from a GUI shortcut, or on
        /// Windows where a user tries to open the binary by double-clicking instead of using the
        /// command line (i.e. set `.arg_required_else_help(true)` and `.wait_on_error(true)` to
        /// display the help in such a case).
        ///
        /// **NOTE:** This setting is **not** recursive with subcommands, meaning if you wish this
        /// behavior for all subcommands, you must set this on each command (needing this is extremely
        /// rare)
        ///
        /// # Examples
        ///
        /// ```no_run
        /// # use clap::{App, Arg, AppSettings};
        /// App::new("myprog")
        ///     .setting(AppSettings::WaitOnError)
        /// # ;
        /// ```
        WaitOnError,
        /// Specifies that the help text should be displayed (and then exit gracefully), if no
        /// subcommands are present at runtime (i.e. an empty run such as, `$ myprog`.
        ///
        /// **NOTE:** This should *not* be used with `.subcommand_required()` as they do the same
        /// thing, except one prints the help text, and one prints an error.
        ///
        /// **NOTE:** If the user specifies arguments at runtime, but no subcommand the help text will
        /// still be displayed and exit. If this is *not* the desired result, consider using
        /// `.arg_required_else_help()`
        ///
        /// # Examples
        ///
        /// ```no_run
        /// # use clap::{App, Arg, AppSettings};
        /// App::new("myprog")
        ///     .setting(AppSettings::SubcommandRequiredElseHelp)
        /// # ;
        /// ```
        SubcommandRequiredElseHelp,
        /// Specifies that this subcommand should be hidden from help messages
        ///
        /// # Examples
        ///
        /// ```no_run
        /// # use clap::{App, Arg, AppSettings, SubCommand};
        /// App::new("myprog")
        ///     .subcommand(SubCommand::with_name("test")
        ///     .setting(AppSettings::Hidden))
        /// # ;
        /// ```
        Hidden,
        /// Specifies that the final positional argument is a vararg and that `clap` should not attempt
        /// to parse any further args.
        ///
        /// The values of the trailing positional argument will contain all args from itself on.
        ///
        /// **NOTE:** The final positional argument **must** have `.multiple(true)` or usage token
        /// equivalent.
        ///
        /// # Examples
        ///
        /// ```no_run
        /// # use clap::{App, Arg, AppSettings};
        /// let m = App::new("myprog")
        ///     .setting(AppSettings::TrailingVarArg)
        ///     .arg(Arg::from_usage("<cmd>... 'commands to run'"))
        ///     .get_matches_from(vec!["myprog", "some_command", "-r", "set"]);
        ///
        /// assert_eq!(m.values_of("cmd").unwrap(), &["some_command", "-r", "set"]);
        /// ```
        TrailingVarArg,
        /// Specifies that the parser should not assume the first argument passed is the binary name.
        /// This is normally the case when using a "daemon" style mode, or an interactive CLI where one
        /// one would not normally type the binary or program name for each command.
        ///
        /// **NOTE:** This should only be used when you absolutely know it's what you need. 99% of the
        /// cases out there don't need this setting.
        ///
        /// # Examples
        ///
        /// ```no_run
        /// # use clap::{App, Arg, AppSettings};
        /// let m = App::new("myprog")
        ///     .setting(AppSettings::NoBinaryName)
        ///     .arg(Arg::from_usage("<cmd>... 'commands to run'"))
        ///     .get_matches_from(vec!["some_command", "-r", "set"]);
        ///
        /// assert_eq!(m.values_of("cmd").unwrap(), &["some_command", "-r", "set"]);
        /// ```
        NoBinaryName,
        #[doc(hidden)]
        NeedsLongVersion,
        #[doc(hidden)]
        NeedsLongHelp,
        #[doc(hidden)]
        NeedsSubcommandHelp,
        #[doc(hidden)]
        DisableVersion,
    }

    impl FromStr for AppSettings {
        type Err = String;
        fn from_str(s: &str) -> Result<Self, <Self as FromStr>::Err> {
            match &*s.to_ascii_lowercase() {
                "subcommandsnegatereqs" => Ok(AppSettings::SubcommandsNegateReqs),
                "subcommandsrequired" => Ok(AppSettings::SubcommandRequired),
                "argrequiredelsehelp" => Ok(AppSettings::ArgRequiredElseHelp),
                "globalversion" => Ok(AppSettings::GlobalVersion),
                "versionlesssubcommands" => Ok(AppSettings::VersionlessSubcommands),
                "unifiedhelpmessage" => Ok(AppSettings::UnifiedHelpMessage),
                "waitonerror" => Ok(AppSettings::WaitOnError),
                "subcommandrequiredelsehelp" => Ok(AppSettings::SubcommandRequiredElseHelp),
                "hidden" => Ok(AppSettings::Hidden),
                _ => Err("unknown AppSetting, cannot convert from str".to_owned()),
            }
        }
    }

# Help

## Keyboard Shortcuts

?
  Show this help dialog
S
  Focus the search field
⇤
  Move up in search results
⇥
  Move down in search results
⏎
  Go to active search result

## Search Tricks

Prefix searches with a type followed by a colon (e.g. `fn:`) to restrict the search to a given type.

Accepted types are: `fn`, `mod`, `struct`, `enum`, `trait`, `type`, `macro`, and `const`.

Search functions by type signature (e.g. `vec -> usize` or `* -> vec`)