We need a whole WithFilter class to honor the "doesn't create a new collection" contract even though it seems unlikely to matter much in a collection with max size 1.
Test two objects for inequality.
true
if !(this == that), false otherwise.
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
.
a hash value consistent with ==
The expression x == that
is equivalent to if (x eq null) that eq null else x.equals(that)
.
true
if the receiver object is equivalent to the argument; false
otherwise.
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.
the receiver object.
ClassCastException
if the receiver object is not an instance of the erasure of type T0
.
Create a copy of the receiver object.
The default implementation of the clone
method is platform dependent.
a copy of the receiver object.
Applies the given partial function to the value from this Success
or returns this if this is a Failure
.
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:
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
).
true
if the argument is a reference to the receiver object; false
otherwise.
Inverts this Try
. If this is a Failure
, returns its exception wrapped in a Success
. If this is a Success
, returns a Failure
containing an UnsupportedOperationException
.
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.
Returns the given function applied to the value from this Success
or returns this if this is a Failure
.
Transforms a nested Try
, ie, a Try
of type Try[Try[T]]
, into an un-nested Try
, ie, a Try
of type Try[T]
.
Applies fa
if this is a Failure
or fb
if this is a Success
. If fb
is initially applied and throws an exception, then fa
is applied with this exception.
the function to apply if this is a Failure
the function to apply if this is a Success
the results of applying the function
Applies the given function f
if this is a Success
, otherwise returns Unit
if this is a Failure
.
Note: If f
throws, then this method may throw an exception.
Returns string formatted according to given format
string. Format strings are as for String.format
(@see java.lang.String.format).
Returns the value from this Success
or throws the exception if this is a Failure
.
Returns the runtime class representation of the object.
a class object corresponding to the runtime type of the receiver.
Returns the value from this Success
or the given default
argument if this is a Failure
.
Note:: This will throw an exception if it is not a success and default throws an exception.
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.
true
if the receiver object is an instance of erasure of type T0
; false
otherwise.
Maps the given function to the value from this Success
or returns this if this is a Failure
.
Equivalent to !(this eq that)
.
true
if the argument is not a reference to the receiver object; false
otherwise.
Wakes up a single thread that is waiting on the receiver object's monitor.
not specified by SLS as a member of AnyRef
Wakes up all threads that are waiting on the receiver object's monitor.
not specified by SLS as a member of AnyRef
Returns this Try
if it's a Success
or the given default
argument if this is a Failure
.
An iterator over the names of all the elements of this product.
Applies the given function f
if this is a Failure
, otherwise returns this if this is a Success
. This is like map for the exception.
Applies the given function f
if this is a Failure
, otherwise returns this if this is a Success
. This is like flatMap
for the exception.
Returns Left
with Throwable
if this is a Failure
, otherwise returns Right
with Success
value.
Returns None
if this is a Failure
or a Some
containing the value if this is a Success
.
Completes this Try
by applying the function f
to this if this is of type Failure
, or conversely, by applying s
if this is a Success
.
Creates a non-strict filter, which eventually converts this to a Failure
if the predicate is not satisfied.
Note: unlike filter, withFilter does not create a new Try. Instead, it restricts the domain of subsequent map
, flatMap
, foreach
, and withFilter
operations.
As Try is a one-element collection, this may be a bit overkill, but it's consistent with withFilter on Option and the other collections.
the predicate used to test elements.
an object of class WithFilter
, which supports map
, flatMap
, foreach
, and withFilter
operations. All these operations apply to those elements of this Try which satisfy the predicate p
.
© 2002-2019 EPFL, with contributions from Lightbend.
Licensed under the Apache License, Version 2.0.
https://www.scala-lang.org/api/2.13.0/scala/util/Failure.html