Struct rustc_middle::traits::specialization_graph::Graph

pub struct Graph {
    pub parent: DefIdMap<DefId>,
    pub children: DefIdMap<Children>,
    pub has_errored: bool,
}

A per-trait graph of impls in specialization order. At the moment, this graph forms a tree rooted with the trait itself, with all other nodes representing impls, and parent-child relationships representing specializations.

The graph provides two key services:

• Construction. This implicitly checks for overlapping impls (i.e., impls that overlap but where neither specializes the other – an artifact of the simple “chain” rule.

• Parent extraction. In particular, the graph can give you the immediate parents of a given specializing impl, which is needed for extracting default items amongst other things. In the simple “chain” rule, every impl has at most one parent.

Fields

parent: DefIdMap<DefId>

All impls have a parent; the “root” impls have as their parent the def_id of the trait.

children: DefIdMap<Children>

The “root” impls are found by looking up the trait’s def_id.

has_errored: bool

Whether an error was emitted while constructing the graph.

Implementations

impl Graph

pub fn new() -> Graph

pub fn parent(&self, child: DefId) -> DefId

The parent of a given impl, which is the DefId of the trait when the impl is a “specialization root”.

Trait Implementations

impl Debug for Graph

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

Formats the value using the given formatter.

impl<'tcx, __D: TyDecoder<'tcx>> Decodable<__D> for Graph

fn decode(__decoder: &mut __D) -> Result<Self, <__D as Decoder>::Error>

impl<'tcx, __E: TyEncoder<'tcx>> Encodable<__E> for Graph

fn encode(&self, __encoder: &mut __E) -> Result<(), <__E as Encoder>::Error>

impl<'__ctx> HashStable<StableHashingContext<'__ctx>> for Graph

fn hash_stable(
    &self,
    __hcx: &mut StableHashingContext<'__ctx>,
    __hasher: &mut StableHasher
)