rust/crates/hir_ty/src/walk.rs
Florian Diebold d992736e79 Remove unused
2021-04-08 14:36:14 +02:00

151 lines
3.8 KiB
Rust

//! The `TypeWalk` trait (probably to be replaced by Chalk's `Fold` and
//! `Visit`).
use chalk_ir::interner::HasInterner;
use crate::{
AliasEq, AliasTy, Binders, CallableSig, FnSubst, GenericArg, GenericArgData, Interner,
OpaqueTy, ProjectionTy, Substitution, TraitRef, Ty, TyKind, WhereClause,
};
/// This allows walking structures that contain types to do something with those
/// types, similar to Chalk's `Fold` trait.
pub trait TypeWalk {
fn walk(&self, f: &mut impl FnMut(&Ty));
}
impl TypeWalk for Ty {
fn walk(&self, f: &mut impl FnMut(&Ty)) {
match self.kind(&Interner) {
TyKind::Alias(AliasTy::Projection(p_ty)) => {
for t in p_ty.substitution.iter(&Interner) {
t.walk(f);
}
}
TyKind::Alias(AliasTy::Opaque(o_ty)) => {
for t in o_ty.substitution.iter(&Interner) {
t.walk(f);
}
}
TyKind::Dyn(dyn_ty) => {
for p in dyn_ty.bounds.skip_binders().interned().iter() {
p.walk(f);
}
}
TyKind::Slice(ty)
| TyKind::Array(ty, _)
| TyKind::Ref(_, _, ty)
| TyKind::Raw(_, ty) => {
ty.walk(f);
}
TyKind::Function(fn_pointer) => {
fn_pointer.substitution.0.walk(f);
}
TyKind::Adt(_, substs)
| TyKind::FnDef(_, substs)
| TyKind::Tuple(_, substs)
| TyKind::OpaqueType(_, substs)
| TyKind::AssociatedType(_, substs)
| TyKind::Closure(.., substs) => {
substs.walk(f);
}
_ => {}
}
f(self);
}
}
impl<T: TypeWalk> TypeWalk for Vec<T> {
fn walk(&self, f: &mut impl FnMut(&Ty)) {
for t in self {
t.walk(f);
}
}
}
impl TypeWalk for OpaqueTy {
fn walk(&self, f: &mut impl FnMut(&Ty)) {
self.substitution.walk(f);
}
}
impl TypeWalk for ProjectionTy {
fn walk(&self, f: &mut impl FnMut(&Ty)) {
self.substitution.walk(f);
}
}
impl TypeWalk for AliasTy {
fn walk(&self, f: &mut impl FnMut(&Ty)) {
match self {
AliasTy::Projection(it) => it.walk(f),
AliasTy::Opaque(it) => it.walk(f),
}
}
}
impl TypeWalk for GenericArg {
fn walk(&self, f: &mut impl FnMut(&Ty)) {
match &self.interned() {
GenericArgData::Ty(ty) => {
ty.walk(f);
}
_ => {}
}
}
}
impl TypeWalk for Substitution {
fn walk(&self, f: &mut impl FnMut(&Ty)) {
for t in self.iter(&Interner) {
t.walk(f);
}
}
}
impl<T: TypeWalk + HasInterner<Interner = Interner>> TypeWalk for Binders<T> {
fn walk(&self, f: &mut impl FnMut(&Ty)) {
self.skip_binders().walk(f);
}
}
impl TypeWalk for TraitRef {
fn walk(&self, f: &mut impl FnMut(&Ty)) {
self.substitution.walk(f);
}
}
impl TypeWalk for WhereClause {
fn walk(&self, f: &mut impl FnMut(&Ty)) {
match self {
WhereClause::Implemented(trait_ref) => trait_ref.walk(f),
WhereClause::AliasEq(alias_eq) => alias_eq.walk(f),
_ => {}
}
}
}
impl TypeWalk for CallableSig {
fn walk(&self, f: &mut impl FnMut(&Ty)) {
for t in self.params_and_return.iter() {
t.walk(f);
}
}
}
impl TypeWalk for AliasEq {
fn walk(&self, f: &mut impl FnMut(&Ty)) {
self.ty.walk(f);
match &self.alias {
AliasTy::Projection(projection_ty) => projection_ty.walk(f),
AliasTy::Opaque(opaque) => opaque.walk(f),
}
}
}
impl TypeWalk for FnSubst<Interner> {
fn walk(&self, f: &mut impl FnMut(&Ty)) {
self.0.walk(f)
}
}