Add InternedString::with2.

This lets comparisons occur with a single access to the interner,
instead of two.
This commit is contained in:
Nicholas Nethercote 2019-05-09 11:45:56 +10:00
parent 33cde4aac2
commit 8c465b4efa

View file

@ -725,6 +725,15 @@ impl InternedString {
unsafe { f(&*str) }
}
fn with2<F: FnOnce(&str, &str) -> R, R>(self, other: &InternedString, f: F) -> R {
let (self_str, other_str) = with_interner(|interner| {
(interner.get(self.symbol) as *const str,
interner.get(other.symbol) as *const str)
});
// This is safe for the same reason that `with` is safe.
unsafe { f(&*self_str, &*other_str) }
}
pub fn as_symbol(self) -> Symbol {
self.symbol
}
@ -745,7 +754,7 @@ impl PartialOrd<InternedString> for InternedString {
if self.symbol == other.symbol {
return Some(Ordering::Equal);
}
self.with(|self_str| other.with(|other_str| self_str.partial_cmp(other_str)))
self.with2(other, |self_str, other_str| self_str.partial_cmp(other_str))
}
}
@ -754,7 +763,7 @@ impl Ord for InternedString {
if self.symbol == other.symbol {
return Ordering::Equal;
}
self.with(|self_str| other.with(|other_str| self_str.cmp(&other_str)))
self.with2(other, |self_str, other_str| self_str.cmp(other_str))
}
}