Expand description
This crate provides the EnumLike
trait, which defines a mapping from
a given type to usize
.
This is similar to std::mem::discriminant
, however it has a few
differences. First of all, all the values are consecutive starting from
zero. This means that if an enum has 10 variants, the discriminant will
always be lower than 10. If a field has an explicit discriminant, that
value is ignored: in
enum { A = 100 }
, A
will have the value of 0.
And most importantly, this trait allows to create
an instance of the type from the usize
, because the enum data, if present,
is also encoded in the discriminant (if possible). For example:
enum ABC { A, B, C }
enum DEF { D, E, F }
enum AD { A(ABC), D(DEF) }
The AD
enum has 2 variants, but since each of these variants is an enum
with 3 variants, the AD::values().count()
will return 6 instead of 2.
Structs§
- Packed
U8 - Packs an
EnumLike
value into au8
, if possible - Packed
U16 - Packs an
EnumLike
value into au16
, if possible - Values
- Iterator over the values (variants) of
T
Traits§
- Enum
Like - The
EnumLike
trait specifies how a type will be stored inside theEnumVec
. - Enum
Values - Helper trait to iterate over all the possible values of an enum.
Note: you don’t need to implement this trait, it is provided by
EnumLike
.