rust/compiler/rustc_ty/src/common_traits.rs
2020-08-30 18:45:07 +03:00

42 lines
1.3 KiB
Rust

//! Queries for checking whether a type implements one of a few common traits.
use rustc_hir::lang_items::LangItem;
use rustc_infer::infer::TyCtxtInferExt;
use rustc_middle::ty::{self, Ty, TyCtxt};
use rustc_span::DUMMY_SP;
use rustc_trait_selection::traits;
fn is_copy_raw<'tcx>(tcx: TyCtxt<'tcx>, query: ty::ParamEnvAnd<'tcx, Ty<'tcx>>) -> bool {
is_item_raw(tcx, query, LangItem::Copy)
}
fn is_sized_raw<'tcx>(tcx: TyCtxt<'tcx>, query: ty::ParamEnvAnd<'tcx, Ty<'tcx>>) -> bool {
is_item_raw(tcx, query, LangItem::Sized)
}
fn is_freeze_raw<'tcx>(tcx: TyCtxt<'tcx>, query: ty::ParamEnvAnd<'tcx, Ty<'tcx>>) -> bool {
is_item_raw(tcx, query, LangItem::Freeze)
}
fn is_item_raw<'tcx>(
tcx: TyCtxt<'tcx>,
query: ty::ParamEnvAnd<'tcx, Ty<'tcx>>,
item: LangItem,
) -> bool {
let (param_env, ty) = query.into_parts();
let trait_def_id = tcx.require_lang_item(item, None);
tcx.infer_ctxt().enter(|infcx| {
traits::type_known_to_meet_bound_modulo_regions(
&infcx,
param_env,
ty,
trait_def_id,
DUMMY_SP,
)
})
}
pub(crate) fn provide(providers: &mut ty::query::Providers) {
*providers = ty::query::Providers { is_copy_raw, is_sized_raw, is_freeze_raw, ..*providers };
}