FunctorFilter[F]
allows you to map
and filter out elements simultaneously.
Attributes
- Companion:
- object
- Source:
- FunctorFilter.scala
- Graph
- Supertypes
- Known subtypes
- trait TraverseFilter[F]
Members list
Value members
Abstract methods
Attributes
- Source:
- FunctorFilter.scala
A combined map
and filter
. Filtering is handled via Option
instead of Boolean
such that the output type B
can be different than
the input type A
.
A combined map
and filter
. Filtering is handled via Option
instead of Boolean
such that the output type B
can be different than
the input type A
.
Example:
scala> import cats.implicits._
scala> val m: Map[Int, String] = Map(1 -> "one", 3 -> "three")
scala> val l: List[Int] = List(1, 2, 3, 4)
scala> def asString(i: Int): Option[String] = m.get(i)
scala> l.mapFilter(asString)
res0: List[String] = List(one, three)
Attributes
- Source:
- FunctorFilter.scala
Concrete methods
Similar to mapFilter but uses a partial function instead of a function
that returns an Option
.
Similar to mapFilter but uses a partial function instead of a function
that returns an Option
.
Example:
scala> import cats.implicits._
scala> val l: List[Int] = List(1, 2, 3, 4)
scala> FunctorFilter[List].collect(l){
| case 1 => "one"
| case 3 => "three"
| }
res0: List[String] = List(one, three)
Attributes
- Source:
- FunctorFilter.scala
Apply a filter to a structure such that the output structure contains all
A
elements in the input structure that satisfy the predicate f
but none
that don't.
Apply a filter to a structure such that the output structure contains all
A
elements in the input structure that satisfy the predicate f
but none
that don't.
Attributes
- Source:
- FunctorFilter.scala
Apply a filter to a structure such that the output structure contains all
A
elements in the input structure that do not satisfy the predicate f
.
Apply a filter to a structure such that the output structure contains all
A
elements in the input structure that do not satisfy the predicate f
.
Attributes
- Source:
- FunctorFilter.scala
"Flatten" out a structure by collapsing Option
s.
Equivalent to using mapFilter
with identity
.
"Flatten" out a structure by collapsing Option
s.
Equivalent to using mapFilter
with identity
.
Example:
scala> import cats.implicits._
scala> val l: List[Option[Int]] = List(Some(1), None, Some(3), None)
scala> l.flattenOption
res0: List[Int] = List(1, 3)
Attributes
- Source:
- FunctorFilter.scala