Enum ConstantKind

pub(crate) enum ConstantKind {
    TyConst {
        expr: Box<str>,
    },
    Path {
        path: Box<str>,
    },
    Anonymous {
        body: BodyId,
    },
    Extern {
        def_id: DefId,
    },
    Local {
        def_id: DefId,
        body: BodyId,
    },
}

Variants

TyConst

This is the wrapper around ty::Const for a non-local constant. Because it doesn’t have a BodyId, we need to handle it on its own.

Note that ty::Const includes generic parameters, and may not always be uniquely identified by a DefId. So this field must be different from Extern.

Fields

expr: Box<str>

Path

A constant that is just a path (i.e., referring to a const param, free const, etc.).

Fields

path: Box<str>

Anonymous

A constant (expression) that’s not an item or associated item. These are usually found nested inside types (e.g., array lengths) or expressions (e.g., repeat counts), and also used to define explicit discriminant values for enum variants.

Fields

body: BodyId

Extern

A constant from a different crate.

Fields

def_id: DefId

Local

const FOO: u32 = ...;

Fields

def_id: DefId

body: BodyId

Implementations

impl ConstantKind

pub(crate) fn expr(&self, tcx: TyCtxt<'_>) -> String

pub(crate) fn value(&self, tcx: TyCtxt<'_>) -> Option<String>

pub(crate) fn is_literal(&self, tcx: TyCtxt<'_>) -> bool

impl ConstantKind

pub(crate) fn print(&self, tcx: TyCtxt<'_>) -> impl Display + '_

Trait Implementations

impl Clone for ConstantKind

fn clone(&self) -> ConstantKind

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ConstantKind

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

Formats the value using the given formatter.

impl FromClean<ConstantKind> for Constant

fn from_clean(constant: ConstantKind, renderer: &JsonRenderer<'_>) -> Self

impl Hash for ConstantKind

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 ConstantKind

fn eq(&self, other: &ConstantKind) -> 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 Eq for ConstantKind

impl StructuralPartialEq for ConstantKind

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 24 bytes

Size for each variant:

• TyConst: 20 bytes
• Path: 20 bytes
• Anonymous: 8 bytes
• Extern: 8 bytes
• Local: 16 bytes