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    use crate::builder::IntoResettable;
    use crate::builder::Str;
    use crate::builder::StyledStr;
    use crate::util::eq_ignore_case;

    /// A possible value of an argument.
    ///
    /// This is used for specifying [possible values] of [Args].
    ///
    /// See also [`PossibleValuesParser`][crate::builder::PossibleValuesParser]
    ///
    /// **NOTE:** Most likely you can use strings, rather than `PossibleValue` as it is only required
    /// to [hide] single values from help messages and shell completions or to attach [help] to
    /// possible values.
    ///
    /// # Examples
    ///
    /// ```rust
    /// # use clap::{Arg, builder::PossibleValue, ArgAction};
    /// let cfg = Arg::new("config")
    ///     .action(ArgAction::Set)
    ///     .value_name("FILE")
    ///     .value_parser([
    ///         PossibleValue::new("fast"),
    ///         PossibleValue::new("slow").help("slower than fast"),
    ///         PossibleValue::new("secret speed").hide(true)
    ///     ]);
    /// ```
    ///
    /// [Args]: crate::Arg
    /// [possible values]: crate::builder::ValueParser::possible_values
    /// [hide]: PossibleValue::hide()
    /// [help]: PossibleValue::help()
    #[derive(Debug, Default, Clone, PartialEq, Eq)]
    pub struct PossibleValue {
        name: Str,
        help: Option<StyledStr>,
        aliases: Vec<Str>, // (name, visible)
        hide: bool,
    }

    impl PossibleValue {
        /// Create a [`PossibleValue`] with its name.
        ///
        /// The name will be used to decide whether this value was provided by the user to an argument.
        ///
        /// **NOTE:** In case it is not [hidden] it will also be shown in help messages for arguments
        /// that use it as a [possible value] and have not hidden them through [`Arg::hide_possible_values(true)`].
        ///
        /// # Examples
        ///
        /// ```rust
        /// # use clap::builder::PossibleValue;
        /// PossibleValue::new("fast")
        /// # ;
        /// ```
        /// [hidden]: PossibleValue::hide
        /// [possible value]: crate::builder::PossibleValuesParser
        /// [`Arg::hide_possible_values(true)`]: crate::Arg::hide_possible_values()
        pub fn new(name: impl Into<Str>) -> Self {
            PossibleValue {
                name: name.into(),
                ..Default::default()
            }
        }

        /// Sets the help description of the value.
        ///
        /// This is typically displayed in completions (where supported) and should be a short, one-line
        /// description.
        ///
        /// # Examples
        ///
        /// ```rust
        /// # use clap::builder::PossibleValue;
        /// PossibleValue::new("slow")
        ///     .help("not fast")
        /// # ;
        /// ```
        #[inline]
        #[must_use]
        pub fn help(mut self, help: impl IntoResettable<StyledStr>) -> Self {
            self.help = help.into_resettable().into_option();
            self
        }

        /// Hides this value from help and shell completions.
        ///
        /// This is an alternative to hiding through [`Arg::hide_possible_values(true)`], if you only
        /// want to hide some values.
        ///
        /// # Examples
        ///
        /// ```rust
        /// # use clap::builder::PossibleValue;
        /// PossibleValue::new("secret")
        ///     .hide(true)
        /// # ;
        /// ```
        /// [`Arg::hide_possible_values(true)`]: crate::Arg::hide_possible_values()
        #[inline]
        #[must_use]
        pub fn hide(mut self, yes: bool) -> Self {
            self.hide = yes;
            self
        }

        /// Sets a *hidden* alias for this argument value.
        ///
        /// # Examples
        ///
        /// ```rust
        /// # use clap::builder::PossibleValue;
        /// PossibleValue::new("slow")
        ///     .alias("not-fast")
        /// # ;
        /// ```
        #[must_use]
        pub fn alias(mut self, name: impl IntoResettable<Str>) -> Self {
            if let Some(name) = name.into_resettable().into_option() {
                self.aliases.push(name);
            } else {
                self.aliases.clear();
            }
            self
        }

        /// Sets multiple *hidden* aliases for this argument value.
        ///
        /// # Examples
        ///
        /// ```rust
        /// # use clap::builder::PossibleValue;
        /// PossibleValue::new("slow")
        ///     .aliases(["not-fast", "snake-like"])
        /// # ;
        /// ```
        #[must_use]
        pub fn aliases(mut self, names: impl IntoIterator<Item = impl Into<Str>>) -> Self {
            self.aliases.extend(names.into_iter().map(|a| a.into()));
            self
        }
    }

    /// Reflection
    impl PossibleValue {
        /// Get the name of the argument value
        #[inline]
        pub fn get_name(&self) -> &str {
            self.name.as_str()
        }

        /// Get the help specified for this argument, if any
        #[inline]
        pub fn get_help(&self) -> Option<&StyledStr> {
            self.help.as_ref()
        }

        /// Get the help specified for this argument, if any and the argument
        /// value is not hidden
        #[inline]
        #[cfg(feature = "help")]
        pub(crate) fn get_visible_help(&self) -> Option<&StyledStr> {
            if !self.hide {
                self.get_help()
            } else {
                None
            }
        }

        /// Report if [`PossibleValue::hide`] is set
        #[inline]
        pub fn is_hide_set(&self) -> bool {
            self.hide
        }

        /// Report if PossibleValue is not hidden and has a help message
        pub(crate) fn should_show_help(&self) -> bool {
            !self.hide && self.help.is_some()
        }

        /// Get the name if argument value is not hidden, `None` otherwise,
        /// but wrapped in quotes if it contains whitespace
        #[cfg(feature = "help")]
        pub(crate) fn get_visible_quoted_name(&self) -> Option<std::borrow::Cow<'_, str>> {
            if !self.hide {
                Some(if self.name.contains(char::is_whitespace) {
                    format!("{:?}", self.name).into()
                } else {
                    self.name.as_str().into()
                })
            } else {
                None
            }
        }

        /// Returns all valid values of the argument value.
        ///
        /// Namely the name and all aliases.
        pub fn get_name_and_aliases(&self) -> impl Iterator<Item = &str> + '_ {
            std::iter::once(self.get_name()).chain(self.aliases.iter().map(|s| s.as_str()))
        }

        /// Tests if the value is valid for this argument value
        ///
        /// The value is valid if it is either the name or one of the aliases.
        ///
        /// # Examples
        ///
        /// ```rust
        /// # use clap::builder::PossibleValue;
        /// let arg_value = PossibleValue::new("fast").alias("not-slow");
        ///
        /// assert!(arg_value.matches("fast", false));
        /// assert!(arg_value.matches("not-slow", false));
        ///
        /// assert!(arg_value.matches("FAST", true));
        /// assert!(!arg_value.matches("FAST", false));
        /// ```
        pub fn matches(&self, value: &str, ignore_case: bool) -> bool {
            if ignore_case {
                self.get_name_and_aliases()
                    .any(|name| eq_ignore_case(name, value))
            } else {
                self.get_name_and_aliases().any(|name| name == value)
            }
        }
    }

    impl<S: Into<Str>> From<S> for PossibleValue {
        fn from(s: S) -> Self {
            Self::new(s)
        }
    }