LeftProjection
Projects an Either into a Left.
Type parameters
- A
-
the type of the
Leftvalue - B
-
the type of the
Rightvalue
Value parameters
- e
-
the
Eithervalue to project
Attributes
- See also
- Source
- Either.scala
- Graph
-
- Supertypes
Members list
Value members
Concrete methods
Returns false if Right or returns the result of the application of the given function to the Left value.
Returns false if Right or returns the result of the application of the given function to the Left value.
Left(12).left.exists(_ > 10) // true
Left(7).left.exists(_ > 10) // false
Right(12).left.exists(_ > 10) // false
Value parameters
- p
-
the predicate to apply to the
Leftvalue
Attributes
- Returns
-
trueif this is aLeftand the predicate holds for its value - Source
- Either.scala
Returns None if this is a Right or if the given predicate p does not hold for the left value, otherwise, returns a Left.
Returns None if this is a Right or if the given predicate p does not hold for the left value, otherwise, returns a Left.
Left(12).left.filterToOption(_ > 10) // Some(Left(12))
Left(7).left.filterToOption(_ > 10) // None
Right(12).left.filterToOption(_ > 10) // None
Type parameters
- B1
-
the right type of the resulting
Either
Value parameters
- p
-
the predicate to apply to the
Leftvalue
Attributes
- Returns
-
Some(Left(value))if this is aLeftand the predicate holds,Noneotherwise - Source
- Either.scala
Binds the given function across Left.
Binds the given function across Left.
Left(12).left.flatMap(x => Left("scala")) // Left("scala")
Right(12).left.flatMap(x => Left("scala")) // Right(12)
Type parameters
- A1
-
the left type of the resulting
Either - B1
-
the supertype of
Bused to widen the right type
Value parameters
- f
-
the function to bind across
Left
Attributes
- Returns
-
the result of applying
fif this is aLeft, otherwise the unchangedRight - Source
- Either.scala
Returns true if Right or returns the result of the application of the given function to the Left value.
Returns true if Right or returns the result of the application of the given function to the Left value.
Left(12).left.forall(_ > 10) // true
Left(7).left.forall(_ > 10) // false
Right(12).left.forall(_ > 10) // true
Value parameters
- p
-
the predicate to apply to the
Leftvalue
Attributes
- Returns
-
trueif this is aRightor the predicate holds for theLeftvalue - Source
- Either.scala
Executes the given side-effecting function if this is a Left.
Executes the given side-effecting function if this is a Left.
Left(12).left.foreach(x => println(x)) // prints "12"
Right(12).left.foreach(x => println(x)) // doesn't print
Type parameters
- U
-
the return type of the side-effecting function (discarded)
Value parameters
- f
-
the side-effecting function to execute
Attributes
- Source
- Either.scala
Returns the value from this Left or the given argument if this is a Right.
Returns the value from this Left or the given argument if this is a Right.
Left(12).left.getOrElse(17) // 12
Right(12).left.getOrElse(17) // 17
Type parameters
- A1
-
the supertype of
Aused to widen the return type
Value parameters
- or
-
the default value to return if this is a
Right, evaluated lazily
Attributes
- Returns
-
the
Leftvalue if present, otherwiseor - Source
- Either.scala
Maps the function argument through Left.
Maps the function argument through Left.
Left(12).left.map(_ + 2) // Left(14)
Right[Int, Int](12).left.map(_ + 2) // Right(12)
Type parameters
- A1
-
the result type of the mapping function
Value parameters
- f
-
the function to apply to the
Leftvalue
Attributes
- Returns
-
a new
Eitherwith the function applied if this is aLeft, otherwise the unchangedRight - Source
- Either.scala
Returns a Some containing the Left value if it exists or a None if this is a Right.
Returns a Some containing the Left value if it exists or a None if this is a Right.
Left(12).left.toOption // Some(12)
Right(12).left.toOption // None
Attributes
- Returns
-
a
Somecontaining theLeftvalue, orNoneif this is aRight - Source
- Either.scala
Returns a Seq containing the Left value if it exists or an empty Seq if this is a Right.
Returns a Seq containing the Left value if it exists or an empty Seq if this is a Right.
Left(12).left.toSeq // Seq(12)
Right(12).left.toSeq // Seq()
Attributes
- Returns
-
a
Seqcontaining theLeftvalue, or an emptySeqif this is aRight - Source
- Either.scala
Deprecated methods
Returns None if this is a Right or if the given predicate p does not hold for the left value, otherwise, returns a Left.
Returns None if this is a Right or if the given predicate p does not hold for the left value, otherwise, returns a Left.
Left(12).left.filter(_ > 10) // Some(Left(12))
Left(7).left.filter(_ > 10) // None
Right(12).left.filter(_ > 10) // None
Attributes
- Deprecated
-
[Since version 2.13.0]Use `filterToOption`, which more accurately reflects the return type - Source
- Either.scala
Returns the value from this Left or throws NoSuchElementException if this is a Right.
Returns the value from this Left or throws NoSuchElementException if this is a Right.
Left(12).left.get // 12
Right(12).left.get // NoSuchElementException
Attributes
- Throws
-
NoSuchElementException
if the projection is scala.util.Right
- Deprecated
-
[Since version 2.13.0]use `Either.swap.getOrElse` instead - Source
- Either.scala
Inherited methods
An iterator over the names of all the elements of this product.
An iterator over the names of all the elements of this product.
Attributes
- Inherited from:
- Product
- Source
- Product.scala
An iterator over all the elements of this product.
An iterator over all the elements of this product.
Attributes
- Returns
-
in the default implementation, an
Iterator[Any] - Inherited from:
- Product
- Source
- Product.scala