Enum ArgumentValue 

pub enum ArgumentValue {
    Scalar(String),
    List(Vec<String>),
}

One value supplied for a declared parameter.

Two shapes, because a caller can SUPPLY two shapes — but only one of them renders. A command parameter is one command-line word, so a single value becomes that word; a list has no rendering at all and is refused by name, with both shapes stated, before any argv exists (super::DeclaredCommandContract::render). The list shape is carried here precisely so that refusal can see it and say what arrived, rather than joining it into a string nobody wrote.

Variants

Scalar(String)

A single value, rendered as written.

List(Vec<String>)

Several values supplied at once, which no declared parameter accepts: carried so the refusal can name the shape that arrived.

Implementations

impl ArgumentValue

pub fn scalar(value: impl Into<String>) -> Self

A scalar from anything string-like.

pub fn list<I, S>(values: I) -> Self

where I: IntoIterator<Item = S>, S: Into<String>,

A list from an iterator of string-likes.

pub fn describe(&self) -> String

How a diagnostic names this value, without pretending a list is a string.

pub fn from_json(parameter: &str, value: &Value) -> Result<Self, RenderError>

The argument value a JSON dispatch input carries for parameter.

Strings, numbers and booleans have one obvious argument spelling and take it. An array becomes a list, provided every item is itself one of those three. null and an object have no single obvious spelling — guessing one (empty string? JSON text? space-joined?) would make the command mean something the author never wrote — so each is refused by name.

Errors

Returns RenderError::UnrepresentableValue for a value with no unambiguous argument form, and RenderError::InteriorNul for a string carrying a NUL byte, which the kernel would silently truncate the argument at.

Trait Implementations

impl Clone for ArgumentValue

fn clone(&self) -> ArgumentValue

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ArgumentValue

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

Formats the value using the given formatter.

impl Eq for ArgumentValue

impl PartialEq for ArgumentValue

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ArgumentValue