Enum IdentifierType

pub enum IdentifierType {
    Junk,
    Global,
    Instance,
    Class,
    AttrSet,
    Constant,
    Local,
}

Valid types for Ruby identifiers.

Spinoso symbol parses byte strings to determine if they are valid idents for the Inspect iterator (which requires the inspect Cargo feature to be enabled). Symbols that are valid idents do not get wrapped in " when generating their debug output.

See variant documentation for the set of ident types.

IdentifierType’s primary interface is through the TryFrom and FromStr conversion traits. Parsing &str and &[u8] is supported.

Examples – local variable

assert_eq!(
    "spinoso".parse::<IdentifierType>(),
    Ok(IdentifierType::Local)
);
assert_eq!(
    "spinoso_symbol_features".parse::<IdentifierType>(),
    Ok(IdentifierType::Local)
);

Examples – constant

assert_eq!(
    "Spinoso".parse::<IdentifierType>(),
    Ok(IdentifierType::Constant)
);
assert_eq!(
    "SpinosoSymbol".parse::<IdentifierType>(),
    Ok(IdentifierType::Constant)
);
assert_eq!(
    "SPINOSO_SYMBOL_FEATURES".parse::<IdentifierType>(),
    Ok(IdentifierType::Constant)
);

Examples – global

assert_eq!(
    "$use_spinoso_symbol".parse::<IdentifierType>(),
    Ok(IdentifierType::Global)
);
assert_eq!(
    "$USE_SPINOSO_SYMBOL".parse::<IdentifierType>(),
    Ok(IdentifierType::Global)
);

Examples – instance and class variables

assert_eq!(
    "@artichoke".parse::<IdentifierType>(),
    Ok(IdentifierType::Instance)
);
assert_eq!(
    "@@rumble".parse::<IdentifierType>(),
    Ok(IdentifierType::Class)
);

Example – attribute setter

Attribute setters are local idents that end in =.

assert_eq!(
    "artichoke=".parse::<IdentifierType>(),
    Ok(IdentifierType::AttrSet)
);
assert_eq!(
    "spinoso_symbol=".parse::<IdentifierType>(),
    Ok(IdentifierType::AttrSet)
);

Variants

Junk

Identifier that contains “junk”.

Junk mostly equates to non-sigil ASCII symbols. Identifiers like empty? and flatten! are junk idents. All special symbolic Ruby methods like <=> and !~ are junk identifiers.

Examples

assert_eq!("empty?".parse::<IdentifierType>(), Ok(IdentifierType::Junk));
assert_eq!(
    "flatten!".parse::<IdentifierType>(),
    Ok(IdentifierType::Junk)
);
assert_eq!("<=>".parse::<IdentifierType>(), Ok(IdentifierType::Junk));
assert_eq!("!~".parse::<IdentifierType>(), Ok(IdentifierType::Junk));
assert_eq!("[]".parse::<IdentifierType>(), Ok(IdentifierType::Junk));
assert_eq!("[]=".parse::<IdentifierType>(), Ok(IdentifierType::Junk));
assert_eq!("=~".parse::<IdentifierType>(), Ok(IdentifierType::Junk));
assert_eq!("==".parse::<IdentifierType>(), Ok(IdentifierType::Junk));
assert_eq!("===".parse::<IdentifierType>(), Ok(IdentifierType::Junk));

Global

Identifier that is a global variable name.

Global variables are prefixed with the sigil $. There are two types of global variables:

• $ followed by a IdentifierType::Ident sequence.
• Special global variables, which include Regexp globals ($1..$9) and $-w type globals.

Examples

assert_eq!(
    "$".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);
assert_eq!("$foo".parse::<IdentifierType>(), Ok(IdentifierType::Global));
assert_eq!(
    "$@foo".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);
assert_eq!("$0".parse::<IdentifierType>(), Ok(IdentifierType::Global));
assert_eq!("$1".parse::<IdentifierType>(), Ok(IdentifierType::Global));
assert_eq!("$9".parse::<IdentifierType>(), Ok(IdentifierType::Global));
assert_eq!("$-w".parse::<IdentifierType>(), Ok(IdentifierType::Global));
assert_eq!(
    "$-www".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);

Instance

Identifier that is an instance variable name.

Instance variables are prefixed with a single @ sigil. The remaining bytes must be a valid Constant or Local ident.

Examples

assert_eq!(
    "@".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);
assert_eq!(
    "@foo".parse::<IdentifierType>(),
    Ok(IdentifierType::Instance)
);
assert_eq!(
    "@Foo".parse::<IdentifierType>(),
    Ok(IdentifierType::Instance)
);
assert_eq!(
    "@FOO".parse::<IdentifierType>(),
    Ok(IdentifierType::Instance)
);
assert_eq!(
    "@foo_bar".parse::<IdentifierType>(),
    Ok(IdentifierType::Instance)
);
assert_eq!(
    "@FooBar".parse::<IdentifierType>(),
    Ok(IdentifierType::Instance)
);
assert_eq!(
    "@FOO_BAR".parse::<IdentifierType>(),
    Ok(IdentifierType::Instance)
);
assert_eq!(
    "@$foo".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);
assert_eq!(
    "@0".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);
assert_eq!(
    "@1".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);
assert_eq!(
    "@9".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);

Class

Identifier that is a class variable name.

Class variables are prefixed with a double @@ sigil. The remaining bytes must be a valid Constant or Local ident.

Examples

assert_eq!(
    "@@".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);
assert_eq!("@@foo".parse::<IdentifierType>(), Ok(IdentifierType::Class));
assert_eq!("@@Foo".parse::<IdentifierType>(), Ok(IdentifierType::Class));
assert_eq!("@@FOO".parse::<IdentifierType>(), Ok(IdentifierType::Class));
assert_eq!(
    "@@foo_bar".parse::<IdentifierType>(),
    Ok(IdentifierType::Class)
);
assert_eq!(
    "@@FooBar".parse::<IdentifierType>(),
    Ok(IdentifierType::Class)
);
assert_eq!(
    "@@FOO_BAR".parse::<IdentifierType>(),
    Ok(IdentifierType::Class)
);
assert_eq!(
    "@@$foo".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);
assert_eq!(
    "@@0".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);
assert_eq!(
    "@@1".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);
assert_eq!(
    "@@9".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);

AttrSet

Identifier that is an “attribute setter” method name.

AttrSet idents end in the = sigil and are otherwise valid Local or Constant idents. AttrSet idents cannot have any other “junk” symbols.

Examples

assert_eq!(
    "Foo=".parse::<IdentifierType>(),
    Ok(IdentifierType::AttrSet)
);
assert_eq!(
    "foo=".parse::<IdentifierType>(),
    Ok(IdentifierType::AttrSet)
);
assert_eq!(
    "foo_bar=".parse::<IdentifierType>(),
    Ok(IdentifierType::AttrSet)
);
assert_eq!(
    "foo_bar?=".parse::<IdentifierType>(),
    Err(ParseIdentifierError::new())
);
assert_eq!("ω=".parse::<IdentifierType>(), Ok(IdentifierType::AttrSet));

Constant

Identifier that is a constant name.

Constant names can be either ASCII or Unicode and must start with a uppercase character.

Examples

assert_eq!(
    "Foo".parse::<IdentifierType>(),
    Ok(IdentifierType::Constant)
);
assert_eq!(
    "FOO".parse::<IdentifierType>(),
    Ok(IdentifierType::Constant)
);
assert_eq!(
    "FooBar".parse::<IdentifierType>(),
    Ok(IdentifierType::Constant)
);
assert_eq!(
    "FOO_BAR".parse::<IdentifierType>(),
    Ok(IdentifierType::Constant)
);
assert_eq!("Ω".parse::<IdentifierType>(), Ok(IdentifierType::Constant));

Local

Identifier that is a local variable or method name.

Local names can be either ASCII or Unicode and must start with a lowercase character.

Examples

assert_eq!("foo".parse::<IdentifierType>(), Ok(IdentifierType::Local));
assert_eq!("fOO".parse::<IdentifierType>(), Ok(IdentifierType::Local));
assert_eq!(
    "fooBar".parse::<IdentifierType>(),
    Ok(IdentifierType::Local)
);
assert_eq!(
    "foo_bar".parse::<IdentifierType>(),
    Ok(IdentifierType::Local)
);
assert_eq!("ω".parse::<IdentifierType>(), Ok(IdentifierType::Local));

Implementations

impl IdentifierType

pub const fn new() -> Self

Return a new, default IdentifierType.

Prefer to use new() over default() since new() is const.

Examples

const ID_TYPE: IdentifierType = IdentifierType::new();
assert_eq!(ID_TYPE, IdentifierType::Junk);
assert_eq!(ID_TYPE, IdentifierType::default());

Trait Implementations

impl Clone for IdentifierType

fn clone(&self) -> IdentifierType

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for IdentifierType

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

Formats the value using the given formatter.

impl Default for IdentifierType

fn default() -> Self

Construct a “junk” identifier type.

Examples

const ID_TYPE: IdentifierType = IdentifierType::new();
assert_eq!(ID_TYPE, IdentifierType::Junk);
assert_eq!(ID_TYPE, IdentifierType::default());

impl FromStr for IdentifierType

type Err = ParseIdentifierError

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl Hash for IdentifierType

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 Ord for IdentifierType

fn cmp(&self, other: &IdentifierType) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for IdentifierType

fn eq(&self, other: &IdentifierType) -> 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 PartialOrd for IdentifierType

fn partial_cmp(&self, other: &IdentifierType) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl TryFrom<&[u8]> for IdentifierType

type Error = ParseIdentifierError

The type returned in the event of a conversion error.

fn try_from(value: &[u8]) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<&str> for IdentifierType

type Error = ParseIdentifierError

The type returned in the event of a conversion error.

fn try_from(value: &str) -> Result<Self, Self::Error>

Performs the conversion.

impl Copy for IdentifierType

impl Eq for IdentifierType

impl StructuralPartialEq for IdentifierType