Trait scala.collection.generic.IsIterableOnce
Companion object IsIterableOnce


 trait IsIterableOnce[Repr] extends AnyRef



Type class witnessing that a collection representation type Repr has elements of type A and has a conversion to IterableOnce[A].
 This type enables simple enrichment of IterableOnces with extension methods which can make full use of the mechanics of the Scala collections framework in their implementation.
 Example usage,
class FilterMapImpl[Repr, I <: IsIterableOnce[Repr]](coll: Repr, it: I) {
  final def filterMap[B, That](f: it.A => Option[B])(implicit bf: BuildFrom[Repr, B, That]): That = {
    val b = bf.newBuilder(coll)
    for(e <- it(coll).iterator) f(e) foreach (b +=)
    b.result()
  }
}
implicit def filterMap[Repr](coll: Repr)(implicit it: IsIterableOnce[Repr]): FilterMapImpl[Repr, it.type] =
  new FilterMapImpl(coll, it)

List(1, 2, 3, 4, 5) filterMap (i => if(i % 2 == 0) Some(i) else None)
// == List(2, 4)


Source
IsIterableOnce.scala
Since
2.10
Linear Supertypes

AnyRef, Any

Known Subclasses

IsIterable, IsMap, IsSeq





Type Members

abstract  type A

The type of elements we can traverse over (e.g. Int).


Abstract Value Members

abstract  def apply(coll: Repr): IterableOnce[A]



Concrete Value Members

final  def !=(arg0: Any): Boolean


Test two objects for inequality. 

returns
true if !(this == that), false otherwise.


Definition Classes
AnyRef → Any




final  def ##(): Int


Equivalent to x.hashCode except for boxed numeric types and null. For numerics, it returns a hash value which is consistent with value equality: if two value type instances compare as true, then ## will produce the same hash value for each of them. For null returns a hashcode where null.hashCode throws a NullPointerException. 

returns
a hash value consistent with ==


Definition Classes
AnyRef → Any




 def +(other: String): String


Implicit
This member is added by an implicit conversion from IsIterableOnce[Repr] toany2stringadd[IsIterableOnce[Repr]] performed by method any2stringadd in scala.Predef.
Definition Classes
any2stringadd


 def ->[B](y: B): (IsIterableOnce[Repr], B)


Implicit
This member is added by an implicit conversion from IsIterableOnce[Repr] toArrowAssoc[IsIterableOnce[Repr]] performed by method ArrowAssoc in scala.Predef.
Definition Classes
ArrowAssoc
Annotations

@inline() 


final  def ==(arg0: Any): Boolean


The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that). 

returns
true if the receiver object is equivalent to the argument; false otherwise.


Definition Classes
AnyRef → Any




final  def asInstanceOf[T0]: T0



Cast the receiver object to be of type T0.
 Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression 1.asInstanceOf[String] will throw a ClassCastException at runtime, while the expression List(1).asInstanceOf[List[String]] will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested type. 


returns
the receiver object.


Definition Classes
Any
Exceptions thrown
ClassCastException if the receiver object is not an instance of the erasure of type T0.



 def clone(): AnyRef



Create a copy of the receiver object.
 The default implementation of the clone method is platform dependent. 


returns
a copy of the receiver object.


Attributes
protected[java.lang] 
Definition Classes
AnyRef
Annotations

@throws(classOf[java.lang.CloneNotSupportedException]) @native() 
Note
not specified by SLS as a member of AnyRef



 def ensuring(cond: (IsIterableOnce[Repr]) => Boolean, msg: => Any): IsIterableOnce[Repr]


Implicit
This member is added by an implicit conversion from IsIterableOnce[Repr] toEnsuring[IsIterableOnce[Repr]] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring


 def ensuring(cond: (IsIterableOnce[Repr]) => Boolean): IsIterableOnce[Repr]


Implicit
This member is added by an implicit conversion from IsIterableOnce[Repr] toEnsuring[IsIterableOnce[Repr]] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring


 def ensuring(cond: Boolean, msg: => Any): IsIterableOnce[Repr]


Implicit
This member is added by an implicit conversion from IsIterableOnce[Repr] toEnsuring[IsIterableOnce[Repr]] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring


 def ensuring(cond: Boolean): IsIterableOnce[Repr]


Implicit
This member is added by an implicit conversion from IsIterableOnce[Repr] toEnsuring[IsIterableOnce[Repr]] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring


final  def eq(arg0: AnyRef): Boolean



Tests whether the argument (that) is a reference to the receiver object (this).
 The eq method implements an equivalence relation on non-null instances of AnyRef, and has three additional properties:

It is consistent: for any non-null instances x and y of type AnyRef, multiple invocations of x.eq(y) consistently returns true or consistently returns false.For any non-null instance x of type AnyRef, x.eq(null) and null.eq(x) returns false.
null.eq(null) returns true.
 When overriding the equals or hashCode methods, it is important to ensure that their behavior is consistent with reference equality. Therefore, if two objects are references to each other (o1 eq o2), they should be equal to each other (o1 == o2) and they should hash to the same value (o1.hashCode == o2.hashCode). 


returns
true if the argument is a reference to the receiver object; false otherwise.


Definition Classes
AnyRef



 def equals(arg0: AnyRef): Boolean



The equality method for reference types. Default implementation delegates to eq.
 See also equals in scala.Any. 


returns
true if the receiver object is equivalent to the argument; false otherwise.


Definition Classes
AnyRef → Any




 def finalize(): Unit



Called by the garbage collector on the receiver object when there are no more references to the object.
 The details of when and if the finalize method is invoked, as well as the interaction between finalize and non-local returns and exceptions, are all platform dependent. 


Attributes
protected[java.lang] 
Definition Classes
AnyRef
Annotations

@throws(classOf[java.lang.Throwable]) 
Note
not specified by SLS as a member of AnyRef



 def formatted(fmtstr: String): String


Returns string formatted according to given format string. Format strings are as for String.format (@see java.lang.String.format). 

Implicit
This member is added by an implicit conversion from IsIterableOnce[Repr] toStringFormat[IsIterableOnce[Repr]] performed by method StringFormat in scala.Predef.
Definition Classes
StringFormat
Annotations

@inline() 



final  def getClass(): Class[_ <: AnyRef]


Returns the runtime class representation of the object. 

returns
a class object corresponding to the runtime type of the receiver.


Definition Classes
AnyRef → Any

Annotations

@native() 



 def hashCode(): Int


The hashCode method for reference types. See hashCode in scala.Any. 

returns
the hash code value for this object.


Definition Classes
AnyRef → Any

Annotations

@native() 



final  def isInstanceOf[T0]: Boolean



Test whether the dynamic type of the receiver object is T0.
 Note that the result of the test is modulo Scala's erasure semantics. Therefore the expression 1.isInstanceOf[String] will return false, while the expression List(1).isInstanceOf[List[String]] will return true. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the specified type. 


returns
true if the receiver object is an instance of erasure of type T0; false otherwise.


Definition Classes
Any



final  def ne(arg0: AnyRef): Boolean


Equivalent to !(this eq that). 

returns
true if the argument is not a reference to the receiver object; false otherwise.


Definition Classes
AnyRef



final  def notify(): Unit


Wakes up a single thread that is waiting on the receiver object's monitor. 

Definition Classes
AnyRef
Annotations

@native() 
Note
not specified by SLS as a member of AnyRef



final  def notifyAll(): Unit


Wakes up all threads that are waiting on the receiver object's monitor. 

Definition Classes
AnyRef
Annotations

@native() 
Note
not specified by SLS as a member of AnyRef



final  def synchronized[T0](arg0: => T0): T0


Definition Classes
AnyRef


 def toString(): String


Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "@", and the object's hashcode in hexadecimal. 

returns
a String representation of the object.


Definition Classes
AnyRef → Any




final  def wait(): Unit


Definition Classes
AnyRef
Annotations

@throws(classOf[java.lang.InterruptedException]) 


final  def wait(arg0: Long, arg1: Int): Unit


Definition Classes
AnyRef
Annotations

@throws(classOf[java.lang.InterruptedException]) 


final  def wait(arg0: Long): Unit


Definition Classes
AnyRef
Annotations

@throws(classOf[java.lang.InterruptedException]) @native() 





    
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