Enum Arg 

pub enum Arg {
    Null,
    Derived,
    Ref(u64),
    Int(i64),
    Real(f64),
    Str(String),
    Enum(String),
    List(Vec<Arg>),
    Typed(String, Vec<Arg>),
}

One argument of an entity instance.

Variants

Null

$: no value.

Derived

*: value derivable from the schema, not stated.

Ref(u64)

#n: a reference to another instance.

Int(i64)

An integer literal.

Real(f64)

A real literal.

Str(String)

A string literal, with Part 21’s quote doubling undone.

Enum(String)

.NAME.: an enumeration value, without its dots.

List(Vec<Arg>)

A parenthesised list.

Typed(String, Vec<Arg>)

KEYWORD(...) in argument position: a typed (select) value.

Implementations

impl Arg

pub fn reference(&self) -> Option<u64>

The reference this argument carries, if it is one.

pub fn number(&self) -> Option<f64>

The number this argument carries, integer or real.

pub fn list(&self) -> Option<&[Arg]>

The list this argument carries, if it is one.

pub fn is_enum(&self, name: &str) -> bool

Whether this is the enumeration value name.

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

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 StructuralPartialEq for Arg