Enum Feature 

#[non_exhaustive]
pub enum Feature {
    IntegerSubtype,
    EnvSandbox,
    FenvSandbox,
    GotoLabels,
    NativeBitwise,
    Bit32Lib,
    Utf8Lib,
    StringPack,
    CloseAttribute,
    ConstAttribute,
    CoroutineClose,
    WarnFunction,
    TableLenMetamethod,
    GcIsRunning,
    GcParam,
    GlobalKeyword,
    NamedVararg,
    TableCreate,
}

A version-divergent language capability — one present-or-absent row of the support matrix (issue #234). Behavioral divergences (same call, different result — e.g. <=-from-__lt, integer for-loop wraparound, the RNG stream) are deliberately not features: they are resolved inside the core, not gated. Query with LuaVersion::supports.

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.

IntegerSubtype

Integer/float subtypes and math.type — 5.3+.

EnvSandbox

_ENV and load(.., env) lexical-environment sandboxing — 5.2+.

FenvSandbox

setfenv/getfenv function-environment access — 5.1 only.

GotoLabels

goto and ::labels:: — 5.2+.

NativeBitwise

Native bitwise operators & | ~ << >> and integer division // — 5.3+.

Bit32Lib

The bit32 library — 5.2 and 5.3 (removed in 5.4).

Utf8Lib

The utf8 library — 5.3+.

StringPack

string.pack/string.unpack/string.packsize — 5.3+.

CloseAttribute

<close> to-be-closed variables and the __close metamethod — 5.4+.

ConstAttribute

<const> variables — 5.4+.

CoroutineClose

coroutine.close — 5.4+.

WarnFunction

The warn function — 5.4+.

TableLenMetamethod

The __len metamethod honored on tables (not just userdata) — 5.2+.

GcIsRunning

collectgarbage("isrunning") — 5.2+.

GcParam

collectgarbage("param", name [, value]) — 5.5.

GlobalKeyword

The global declaration keyword and declared-global scope model — 5.5.

NamedVararg

Named vararg table parameters function f(a, ...t) — 5.5.

TableCreate

table.create — 5.5.

Implementations

impl Feature

pub const ALL: [Feature; 18]

Every Feature, the iteration source for LuaVersion::features and the matrix-vs-reference test. A match in the test asserts this is exhaustive, so adding a variant without adding it here fails to compile.

pub fn name(self) -> &'static str

A short, stable token naming this feature, used in the fixture and in the Unsupported error message.

Trait Implementations

impl Clone for Feature

fn clone(&self) -> Feature

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Feature

impl Debug for Feature

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

Formats the value using the given formatter.

impl Display for Feature

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

Formats the value using the given formatter.

impl Eq for Feature

impl Hash for Feature

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 Feature

fn eq(&self, other: &Feature) -> 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 Feature