Merge pull request #352 from jgallagher/fix-coherence-issue

merge coherence issue fix
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gwenn 2018-05-12 10:30:57 +02:00 committed by GitHub
commit 89f38b4098
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@ -15,6 +15,8 @@ pub enum ToSqlOutput<'a> {
ZeroBlob(i32), ZeroBlob(i32),
} }
// Generically allow any type that can be converted into a ValueRef
// to be converted into a ToSqlOutput as well.
impl<'a, T: ?Sized> From<&'a T> for ToSqlOutput<'a> impl<'a, T: ?Sized> From<&'a T> for ToSqlOutput<'a>
where &'a T: Into<ValueRef<'a>> where &'a T: Into<ValueRef<'a>>
{ {
@ -23,11 +25,31 @@ impl<'a, T: ?Sized> From<&'a T> for ToSqlOutput<'a>
} }
} }
impl<'a, T: Into<Value>> From<T> for ToSqlOutput<'a> { // We cannot also generically allow any type that can be converted
fn from(t: T) -> Self { // into a Value to be converted into a ToSqlOutput because of
ToSqlOutput::Owned(t.into()) // coherence rules (https://github.com/rust-lang/rust/pull/46192),
// so we'll manually implement it for all the types we know can
// be converted into Values.
macro_rules! from_value(
($t:ty) => (
impl<'a> From<$t> for ToSqlOutput<'a> {
fn from(t: $t) -> Self { ToSqlOutput::Owned(t.into())}
} }
} )
);
from_value!(String);
from_value!(Null);
from_value!(bool);
from_value!(i8);
from_value!(i16);
from_value!(i32);
from_value!(i64);
from_value!(isize);
from_value!(u8);
from_value!(u16);
from_value!(u32);
from_value!(f64);
from_value!(Vec<u8>);
impl<'a> ToSql for ToSqlOutput<'a> { impl<'a> ToSql for ToSqlOutput<'a> {
fn to_sql(&self) -> Result<ToSqlOutput> { fn to_sql(&self) -> Result<ToSqlOutput> {