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Diffstat (limited to 'src/libs/intertrait/cast_rc.rs')
-rw-r--r-- | src/libs/intertrait/cast_rc.rs | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/src/libs/intertrait/cast_rc.rs b/src/libs/intertrait/cast_rc.rs new file mode 100644 index 0000000..79d8d60 --- /dev/null +++ b/src/libs/intertrait/cast_rc.rs @@ -0,0 +1,34 @@ +/** + * Originally from Intertrait by CodeChain + * + * <https://github.com/CodeChain-io/intertrait> + * <https://crates.io/crates/intertrait/0.2.2> + * + * Licensed under either of + * + * Apache License, Version 2.0 (LICENSE-APACHE or <http://www.apache.org/licenses/LICENSE-2.0>) + * MIT license (LICENSE-MIT or <http://opensource.org/licenses/MIT>) + + * at your option. +*/ +use std::rc::Rc; + +use crate::libs::intertrait::{caster, CastFrom}; + +pub trait CastRc +{ + /// Casts an `Rc` for this trait into that for type `T`. + fn cast<T: ?Sized + 'static>(self: Rc<Self>) -> Result<Rc<T>, Rc<Self>>; +} + +/// A blanket implementation of `CastRc` for traits extending `CastFrom`. +impl<S: ?Sized + CastFrom> CastRc for S +{ + fn cast<T: ?Sized + 'static>(self: Rc<Self>) -> Result<Rc<T>, Rc<Self>> + { + match caster::<T>((*self).type_id()) { + Some(caster) => Ok((caster.cast_rc)(self.rc_any())), + None => Err(self), + } + } +} |