Enum Error 

#[non_exhaustive]
pub enum Error {
    DisplayHelp {
        help: String,
    },
    DisplayVersion {
        version: String,
    },
    DisplaySchema {
        schema: String,
    },
    DisplayCompletion {
        completion: String,
    },
    UnknownFlag {
        token: Vec<u8>,
    },
    MissingValue {
        name: &'static str,
        possible_values: &'static [&'static str],
    },
    UnexpectedValue {
        name: &'static str,
    },
    UnexpectedArgument {
        token: Vec<u8>,
        usage: Option<String>,
    },
    UnknownCommand {
        token: Vec<u8>,
    },
    MissingSubcommand {
        name: &'static str,
    },
    MissingRequired {
        name: &'static str,
    },
    MissingRequiredArguments {
        argument: String,
        usage: String,
    },
    DuplicateArgument {
        name: &'static str,
        usage: Option<String>,
    },
    MissingRequirement {
        name: &'static str,
        required_by: &'static str,
    },
    ConflictingArguments {
        name: &'static str,
        other: &'static str,
    },
    InvalidOneOf {
        arguments: String,
    },
    InvalidAnyOf {
        arguments: String,
    },
    InvalidUtf8 {
        name: &'static str,
        value: Vec<u8>,
    },
    InvalidValue {
        name: &'static str,
        value: String,
        reason: String,
    },
}

A built-in parser action or command-line parsing failure.

Help, version, schema, and completion requests are represented alongside ordinary parsing errors so callers of the try_parse* methods can choose how to handle them.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

DisplayHelp

Generated help requested through the built-in help switch.

Fields

help: String

Fully rendered help text for the selected command scope.

DisplayVersion

Version information requested through the built-in version action.

Fields

version: String

Fully rendered version text for the selected command scope.

DisplaySchema

Machine-readable command schema requested through built-in discovery.

Fields

schema: String

Pretty-printed JSON schema document for the selected command scope.

DisplayCompletion

Dynamic shell-completion output requested through Argx’s private completion protocol.

Fields

completion: String

Completion candidates encoded for the generated shell adapter.

UnknownFlag

A flag-like token did not match any declared flag.

Fields

token: Vec<u8>

Encoded token supplied by the caller.

MissingValue

A flag that consumes a value did not receive one.

Fields

name: &'static str

Canonical user-facing argument label.

possible_values: &'static [&'static str]

Finite values accepted by this option, when known.

UnexpectedValue

A value was attached to a switch that does not accept one.

Fields

name: &'static str

Canonical user-facing argument label.

UnexpectedArgument

A word could not be assigned to any positional argument.

Fields

token: Vec<u8>

Encoded token supplied by the caller.

usage: Option<String>

Corrective usage for the selected command scope, when available.

UnknownCommand

A word did not match any child command when command selection was required.

Fields

token: Vec<u8>

Encoded token supplied by the caller.

MissingSubcommand

A required subcommand field was not selected.

Fields

name: &'static str

Canonical field name.

MissingRequired

A required field was not supplied during generated binding.

Fields

name: &'static str

Canonical user-facing argument label.

MissingRequiredArguments

One or more required arguments were missing from a parsed command invocation.

Fields

argument: String

Canonical CLI rendering of the missing argument.

usage: String

Usage for the selected command scope.

DuplicateArgument

A scalar argument was supplied more than once.

Fields

name: &'static str

Canonical user-facing argument label.

usage: Option<String>

Corrective usage for the selected command scope, when available.

MissingRequirement

An argument required by another supplied argument was not available.

Fields

name: &'static str

Canonical user-facing label of the missing argument.

required_by: &'static str

Canonical user-facing label of the argument imposing the requirement.

ConflictingArguments

Two arguments declared to conflict were supplied together.

Fields

name: &'static str

Canonical user-facing label of the argument declaring the conflict.

other: &'static str

Canonical user-facing label of the conflicting argument.

InvalidOneOf

A one_of set had zero or multiple explicitly supplied members.

Fields

arguments: String

Comma-separated canonical labels of the participating arguments.

InvalidAnyOf

An any_of set had no explicitly supplied member.

Fields

arguments: String

Comma-separated canonical labels of the participating arguments.

InvalidUtf8

A text value was not valid UTF-8.

Fields

name: &'static str

Canonical user-facing argument label.

value: Vec<u8>

Encoded value supplied by the caller.

InvalidValue

A UTF-8 value could not be converted to the field’s Rust type.

Fields

name: &'static str

Canonical user-facing argument label.

value: String

Text supplied on argv.

reason: String

Conversion failure reported by the target type.

Implementations

impl Error

pub const fn exit_code(&self) -> i32

Returns the process status used by Self::exit.

Examples

let help = argx::Error::DisplayHelp { help: String::new() };
let failure = argx::Error::UnknownFlag { token: b"--bad".to_vec() };

assert_eq!(help.exit_code(), 0);
assert_eq!(failure.exit_code(), 2);

pub fn exit(&self) -> !

Prints this result to the appropriate stream and terminates the process.

Help, version, schema, and completion requests are written to standard output and exit successfully. Parse and binding failures are written to standard error and exit with status 2.

Trait Implementations

impl Clone for Error

fn clone(&self) -> Error

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Error

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for Error

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for Error

impl Error for Error

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

impl From<Error> for Error

fn from(source: Error) -> Self

Converts to this type from the input type.

impl PartialEq for Error

fn eq(&self, other: &Error) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Error

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 64 bytes

Size for each variant:

• DisplayHelp: 32 bytes
• DisplayVersion: 32 bytes
• DisplaySchema: 32 bytes
• DisplayCompletion: 32 bytes
• UnknownFlag: 32 bytes
• MissingValue: 40 bytes
• UnexpectedValue: 24 bytes
• UnexpectedArgument: 56 bytes
• UnknownCommand: 32 bytes
• MissingSubcommand: 24 bytes
• MissingRequired: 24 bytes
• MissingRequiredArguments: 56 bytes
• DuplicateArgument: 48 bytes
• MissingRequirement: 40 bytes
• ConflictingArguments: 40 bytes
• InvalidOneOf: 32 bytes
• InvalidAnyOf: 32 bytes
• InvalidUtf8: 48 bytes
• InvalidValue: 64 bytes