Mojo trait
Hashable
A trait for types which specify a function to hash their data.
This hash function will be used for applications like hash maps, and don't need to be cryptographically secure. A good hash function will hash similar / common types to different values, and in particular the low order bits of the hash, which are used in smaller dictionaries, should be sensitive to any changes in the data structure. If your type's hash function doesn't meet this criteria it will get poor performance in common hash map implementations.
from hashlib.hasher import Hasher
@fieldwise_init
struct Foo(Hashable):
var value: Int
fn __hash__[H: Hasher](self, mut hasher: H):
hasher.update(self.value)
var foo = Foo()
print(hash(foo))Implemented traits
AnyType,
UnknownDestructibility
Aliases
__del__is_trivial
alias __del__is_trivial
A flag (often compiler generated) to indicate whether the implementation of __del__ is trivial.
The implementation of __del__ is considered to be trivial if:
- The struct has a compiler-generated trivial destructor and all its fields
have a trivial
__del__method.
In practice, it means that the __del__ can be considered as no-op.
Methods
__hash__
__hash__[H: Hasher](self: _Self, mut hasher: H)
Accepts a hasher and contributes to the hash value by calling the update function of the hasher.
Parameters:
- H (
Hasher): Any Hasher type.
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