Enum ParamType

pub enum ParamType {
    Variable,
    Special(SpecialParam),
    Positional(usize),
}

Type of a parameter

This enum distinguishes three types of parameters: named, special and positional parameters. However, this value does not include the actual parameter name as a string. The actual name is stored in a separate field in the AST node that contains this value.

Note the careful use of the term “name” here. In POSIX terminology, a “name” identifies a named parameter (that is, a variable) and does not include special or positional parameters. An identifier that refers to any kind of parameter is called a “parameter”.

Variants

Variable

Named parameter

Special(SpecialParam)

Special parameter

Positional(usize)

Positional parameter

Positional parameters are indexed starting from 1, so the index of 0 always refers to a non-existent parameter. If the string form of a positional parameter represents an index that is too large to fit in a usize, the index should be usize::MAX, which is also guaranteed to spot a non-existent parameter since a Vec cannot have more than isize::MAX elements.

Trait Implementations

impl Clone for ParamType

fn clone(&self) -> ParamType

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ParamType

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

Formats the value using the given formatter.

impl From<SpecialParam> for ParamType

fn from(special: SpecialParam) -> ParamType

Converts to this type from the input type.

impl Hash for ParamType

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for ParamType

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for ParamType

impl Eq for ParamType

impl StructuralPartialEq for ParamType