Enum Arg 

#[non_exhaustive]
pub enum Arg {
    Positional(Expr),
    Named {
        key: String,
        value: Expr,
    },
    WordAssign {
        key: String,
        value: Expr,
    },
    ShortFlag(String),
    LongFlag(String),
    DoubleDash,
}

A command argument (positional or named).

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.

Positional(Expr)

Positional argument: value

Named

Long flag with attached value: --key=value. Routes through tool_args.named regardless of the receiving command — except past --, where it is an operand and the binders stringify it into one positional "--key=value", the same collapse WordAssign gets there.

Fields

key: String

value: Expr

WordAssign

Bareword shell-assignment in argv position: key=value.

Only commands on the kernel’s shell-assignment allowlist (export, alias) consume this as a named arg; for every other command it’s stringified to a positional "key=value". This matches bash: cat foo=bar opens a file named foo=bar, not a magical key=value.

Fields

key: String

value: Expr

ShortFlag(String)

Short flag: -l, -v (boolean flag)

LongFlag(String)

Long flag: --force, --verbose (boolean flag)

DoubleDash

Double-dash marker: -- - signals end of flags

Trait Implementations

impl Clone for Arg

fn clone(&self) -> Arg

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Arg

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

Formats the value using the given formatter.

impl PartialEq for Arg

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Arg