scalaz.Band which is also commutative, i.e. A + B == B + A
- See also
- Companion
- object
Type members
Classlikes
Inherited classlikes
Band instances must satisfy scalaz.Semigroup.SemigroupLaw and 1 additional law:
Band instances must satisfy scalaz.Semigroup.SemigroupLaw and 1 additional law:
- '''idempotency''':
forall a. append(a, a) == a
- Inherited from
- Band
A semigroup in type F must satisfy two laws:
A semigroup in type F must satisfy two laws:
- '''closure''':
∀ a, b in F, append(a, b)
is also inF
. This is enforced by the type system. - '''associativity''':
∀ a, b, c
inF
, the equationappend(append(a, b), c) = append(a, append(b , c))
holds.
- Inherited from
- Semigroup
Value members
Concrete methods
Inherited methods
The binary operation to combine f1
and f2
.
The binary operation to combine f1
and f2
.
Implementations should not evaluate the by-name parameter f2
if result
can be determined by f1
.
- Inherited from
- Semigroup
An scalaz.Apply, that implements ap
with append
. Note
that the type parameter α
in Apply[λ[α => F]]
is
discarded; it is a phantom type. As such, the functor cannot
support scalaz.Bind.
An scalaz.Apply, that implements ap
with append
. Note
that the type parameter α
in Apply[λ[α => F]]
is
discarded; it is a phantom type. As such, the functor cannot
support scalaz.Bind.
- Inherited from
- Semigroup
Every Semigroup
gives rise to a scalaz.Compose, for which
the type parameters are phantoms.
Every Semigroup
gives rise to a scalaz.Compose, for which
the type parameters are phantoms.
- Note
compose.semigroup
=this
- Inherited from
- Semigroup