Vavr 0.10.6 · io.vavr.Function1 · APIdia, the JavaDoc alternative

Modifier and Type	Field and Description
public static final long	serialVersionUID The serial version uid.

Method Summary

Modifier and Type	Method and Description
public default < return type of after V> Function1<T1, V>	Returns: a function composed of this and after andThen(Function<? super R, ? extends V> the function applied after this after) Overrides default java.util.function.Function.andThen. Returns a composed function that first applies this Function1 to the given argument and then applies Function `after` to the result.
public R	Returns: the result of function application apply(T1 argument 1 t1) Redeclares java.util.function.Function.apply. Applies this function to one argument and returns the result.
public default int	Returns: an int value >= 0 arity() Returns the number of function arguments.
public default < argument type of before V> Function1<V, R>	Returns: a function composed of before and this compose(Function<? super V, ? extends T1> the function applied before this before) Overrides default java.util.function.Function.compose. Returns a composed function that first applies the Function `before` the given argument and then applies this Function1 to the result.
public static < generic parameter type 1 of the resulting function T1, the result type R> Function1<T1, R>	Returns: a function always returning the given value constant(R the value to be returned value) Returns a function that always returns the constant value that you give in parameter.
public default Function1<T1, R>	Returns: a curried function equivalent to this. curried() Returns a curried version of this function.
public static < argument type (and return type) of the identity function T> Function1<T, T>	Returns: the identity Function1 identity() Hides java.util.function.Function.identity. Returns the identity Function1, i.e. the function that returns its input.
public default boolean	Returns: true, if this function is memoizing, false otherwise isMemoized() Checks if this function is memoizing (= caching) computed values.
public static < 1st argument T1, return type R> Function1<T1, Option<R>>	Returns: a function that applies arguments to the given `partialFunction` and returns `Some(result)` if the function is defined for the given arguments, and `None` otherwise. lift(Function<? super T1, ? extends R> a function that is not defined for all values of the domain (e.g. by throwing) partialFunction) Lifts the given `partialFunction` into a total function that returns an `Option` result.
public static < 1st argument T1, return type R> Function1<T1, Try<R>>	Returns: a function that applies arguments to the given `partialFunction` and returns `Success(result)` if the function is defined for the given arguments, and `Failure(throwable)` otherwise. liftTry(Function<? super T1, ? extends R> a function that is not defined for all values of the domain (e.g. by throwing) partialFunction) Lifts the given `partialFunction` into a total function that returns an `Try` result.
public default Function1<T1, R>	Returns: a memoizing function equivalent to this. memoized() Returns a memoizing version of this function, which computes the return value for given arguments only one time.
public static < 1st argument T1, return type R> Function1<T1, R>	Returns: the given `f` instance as narrowed type `Function1<T1, R>` narrow(Function1<? super T1, ? extends R> A `Function1` f) Narrows the given `Function1<?`
public static < 1st argument T1, return type R> Function1<T1, R>	Returns: a `Function1` of(Function1<T1, R> (typically) a method reference, e.g. `Type::method` methodReference) Creates a `Function1` based on method reference lambda expression
public default PartialFunction<T1, R>	Returns: a new `PartialFunction` that has the same behavior like this function but is defined only for those elements that make it through the given `Predicate` partial(Predicate<? super T1> a predicate that states if an element is in the domain of the returned `PartialFunction`. isDefinedAt) Converts this `Function1` to a `PartialFunction` by adding an `isDefinedAt` condition.
public default Function1<T1, R>	Returns: a reversed function equivalent to this. reversed() Returns a reversed version of this function.
public default Function1<Tuple1<T1>, R>	Returns: a tupled function equivalent to this. tupled() Returns a tupled version of this function.

serialVersionUID	back to summary
public static final long serialVersionUID The serial version uid.

Method Detail

andThen back to summary

andThen	back to summary
public default <V> Function1<T1, V> andThen(Function<? super R, ? extends V> after) Overrides default java.util.function.Function.andThen. Returns a composed function that first applies this Function1 to the given argument and then applies Function `after` to the result. Parameters <V> return type of after after:Function<? super R, ? extends V> the function applied after this Returns:Function1<T1, V> a function composed of this and after Exceptions NullPointerException: if after is null

public default <V> Function1<T1, V> andThen(Function<? super R, ? extends V> after)

Overrides default java.util.function.Function.andThen.

Returns a composed function that first applies this Function1 to the given argument and then applies Function after to the result.

Parameters

<V>: return type of after
after:Function<? super R, ? extends V>: the function applied after this

Returns:Function1<T1, V>

a function composed of this and after

Exceptions

NullPointerException:: if after is null

apply	back to summary
public R apply(T1 t1) Redeclares java.util.function.Function.apply. Applies this function to one argument and returns the result. Parameters t1:T1 argument 1 Returns:R the result of function application

apply

back to summary

public R apply(T1 t1)

Redeclares java.util.function.Function.apply.

Applies this function to one argument and returns the result.

Parameters

t1:T1: argument 1

Returns:R

the result of function application

arity	back to summary
public default int arity() Returns the number of function arguments. Returns:int an int value >= 0 See Also Arity

arity

back to summary

public default int arity()

Returns the number of function arguments.

Returns:int: an int value >= 0
See Also: Arity

compose back to summary

compose	back to summary
public default <V> Function1<V, R> compose(Function<? super V, ? extends T1> before) Overrides default java.util.function.Function.compose. Returns a composed function that first applies the Function `before` the given argument and then applies this Function1 to the result. Parameters <V> argument type of before before:Function<? super V, ? extends T1> the function applied before this Returns:Function1<V, R> a function composed of before and this Exceptions NullPointerException: if before is null

public default <V> Function1<V, R> compose(Function<? super V, ? extends T1> before)

Overrides default java.util.function.Function.compose.

Returns a composed function that first applies the Function before the given argument and then applies this Function1 to the result.

Parameters

<V>: argument type of before
before:Function<? super V, ? extends T1>: the function applied before this

Returns:Function1<V, R>

a function composed of before and this

Exceptions

NullPointerException:: if before is null

constant	back to summary
public static <T1, R> Function1<T1, R> constant(R value) Returns a function that always returns the constant value that you give in parameter. Parameters <T1> generic parameter type 1 of the resulting function <R> the result type value:R the value to be returned Returns:Function1<T1, R> a function always returning the given value

constant

back to summary

public static <T1, R> Function1<T1, R> constant(R value)

Returns a function that always returns the constant value that you give in parameter.

Parameters

<T1>: generic parameter type 1 of the resulting function
<R>: the result type
value:R: the value to be returned

Returns:Function1<T1, R>

a function always returning the given value

curried	back to summary
public default Function1<T1, R> curried() Returns a curried version of this function. Returns:Function1<T1, R> a curried function equivalent to this.

curried

back to summary

public default Function1<T1, R> curried()

Returns a curried version of this function.

Returns:Function1<T1, R>: a curried function equivalent to this.

identity	back to summary
public static <T> Function1<T, T> identity() Hides java.util.function.Function.identity. Returns the identity Function1, i.e. the function that returns its input. Parameters <T> argument type (and return type) of the identity function Returns:Function1<T, T> the identity Function1

identity

back to summary

public static <T> Function1<T, T> identity()

Hides java.util.function.Function.identity.

Returns the identity Function1, i.e. the function that returns its input.

Parameters

<T>: argument type (and return type) of the identity function

Returns:Function1<T, T>

the identity Function1

isMemoized	back to summary
public default boolean isMemoized() Checks if this function is memoizing (= caching) computed values. Returns:boolean true, if this function is memoizing, false otherwise

isMemoized

back to summary

public default boolean isMemoized()

Checks if this function is memoizing (= caching) computed values.

Returns:boolean: true, if this function is memoizing, false otherwise

lift back to summary

lift	back to summary
public static <T1, R> Function1<T1, Option<R>> lift(Function<? super T1, ? extends R> partialFunction) Lifts the given `partialFunction` into a total function that returns an `Option` result. Parameters <T1> 1st argument <R> return type partialFunction:Function<? super T1, ? extends R> a function that is not defined for all values of the domain (e.g. by throwing) Returns:Function1<T1, Option<R>> a function that applies arguments to the given `partialFunction` and returns `Some(result)` if the function is defined for the given arguments, and `None` otherwise. Annotations @SuppressWarnings:RedundantTypeArguments

public static <T1, R> Function1<T1, Option<R>> lift(Function<? super T1, ? extends R> partialFunction)

Lifts the given partialFunction into a total function that returns an Option result.

Parameters

<T1>: 1st argument
<R>: return type
partialFunction:Function<? super T1, ? extends R>: a function that is not defined for all values of the domain (e.g. by throwing)

Returns:Function1<T1, Option<R>>

a function that applies arguments to the given partialFunction and returns Some(result) if the function is defined for the given arguments, and None otherwise.

Annotations

@SuppressWarnings:RedundantTypeArguments

liftTry back to summary

liftTry	back to summary
public static <T1, R> Function1<T1, Try<R>> liftTry(Function<? super T1, ? extends R> partialFunction) Lifts the given `partialFunction` into a total function that returns an `Try` result. Parameters <T1> 1st argument <R> return type partialFunction:Function<? super T1, ? extends R> a function that is not defined for all values of the domain (e.g. by throwing) Returns:Function1<T1, Try<R>> a function that applies arguments to the given `partialFunction` and returns `Success(result)` if the function is defined for the given arguments, and `Failure(throwable)` otherwise.

public static <T1, R> Function1<T1, Try<R>> liftTry(Function<? super T1, ? extends R> partialFunction)

Lifts the given partialFunction into a total function that returns an Try result.

Parameters

<T1>: 1st argument
<R>: return type
partialFunction:Function<? super T1, ? extends R>: a function that is not defined for all values of the domain (e.g. by throwing)

Returns:Function1<T1, Try<R>>

a function that applies arguments to the given partialFunction and returns Success(result) if the function is defined for the given arguments, and Failure(throwable) otherwise.

memoized back to summary

memoized	back to summary
public default Function1<T1, R> memoized() Returns a memoizing version of this function, which computes the return value for given arguments only one time. On subsequent calls given the same arguments the memoized value is returned. Please note that memoizing functions do not permit `null` as single argument or return value. Returns:Function1<T1, R> a memoizing function equivalent to this.

public default Function1<T1, R> memoized()

Returns a memoizing version of this function, which computes the return value for given arguments only one time. On subsequent calls given the same arguments the memoized value is returned.

Please note that memoizing functions do not permit null as single argument or return value.

Returns:Function1<T1, R>: a memoizing function equivalent to this.

narrow back to summary

narrow	back to summary
public static <T1, R> Function1<T1, R> narrow(Function1<? super T1, ? extends R> f) Narrows the given `Function1<? super T1, ? extends R>` to `Function1<T1, R>` Parameters <T1> 1st argument <R> return type f:Function1<? super T1, ? extends R> A `Function1` Returns:Function1<T1, R> the given `f` instance as narrowed type `Function1<T1, R>` Annotations @SuppressWarnings:unchecked

public static <T1, R> Function1<T1, R> narrow(Function1<? super T1, ? extends R> f)

Narrows the given Function1<? super T1, ? extends R> to Function1<T1, R>

Parameters

<T1>: 1st argument
<R>: return type
f:Function1<? super T1, ? extends R>: A Function1

Returns:Function1<T1, R>

the given f instance as narrowed type Function1<T1, R>

Annotations

@SuppressWarnings:unchecked

of back to summary

of	back to summary
public static <T1, R> Function1<T1, R> of(Function1<T1, R> methodReference) Creates a `Function1` based on method reference lambda expression Examples (w.l.o.g. referring to Function1): `// using a lambda expression Function1<Integer, Integer> add1 = Function1.of(i -> i + 1); // using a method reference (, e.g. Integer method(Integer i) { return i + 1; }) Function1<Integer, Integer> add2 = Function1.of(this::method); // using a lambda reference Function1<Integer, Integer> add3 = Function1.of(add1::apply);` Caution Reflection loses type information of lambda references. `// type of a lambda expression Type<?, ?> type1 = add1.getType(); // (Integer) -> Integer // type of a method reference Type<?, ?> type2 = add2.getType(); // (Integer) -> Integer // type of a lambda reference Type<?, ?> type3 = add3.getType(); // (Object) -> Object` Parameters <T1> 1st argument <R> return type methodReference:Function1<T1, R> (typically) a method reference, e.g. `Type::method` Returns:Function1<T1, R> a `Function1`

public static <T1, R> Function1<T1, R> of(Function1<T1, R> methodReference)

Creates a Function1 based on

Examples (w.l.o.g. referring to Function1):

// using a lambda expression
Function1<Integer, Integer> add1 = Function1.of(i -> i + 1);

// using a method reference (, e.g. Integer method(Integer i) { return i + 1; })
Function1<Integer, Integer> add2 = Function1.of(this::method);

// using a lambda reference
Function1<Integer, Integer> add3 = Function1.of(add1::apply);

Caution

Reflection loses type information of lambda references.

// type of a lambda expression
Type<?, ?> type1 = add1.getType(); // (Integer) -> Integer

// type of a method reference
Type<?, ?> type2 = add2.getType(); // (Integer) -> Integer

// type of a lambda reference
Type<?, ?> type3 = add3.getType(); // (Object) -> Object

Parameters

<T1>: 1st argument
<R>: return type
methodReference:Function1<T1, R>: (typically) a method reference, e.g. Type::method

Returns:Function1<T1, R>

a Function1

partial back to summary

partial	back to summary
public default PartialFunction<T1, R> partial(Predicate<? super T1> isDefinedAt) Converts this `Function1` to a `PartialFunction` by adding an `isDefinedAt` condition. Parameters isDefinedAt:Predicate<? super T1> a predicate that states if an element is in the domain of the returned `PartialFunction`. Returns:PartialFunction<T1, R> a new `PartialFunction` that has the same behavior like this function but is defined only for those elements that make it through the given `Predicate` Exceptions NullPointerException: if `isDefinedAt` is null

public default PartialFunction<T1, R> partial(Predicate<? super T1> isDefinedAt)

Converts this Function1 to a PartialFunction by adding an isDefinedAt condition.

Parameters

isDefinedAt:Predicate<? super T1>: a predicate that states if an element is in the domain of the returned PartialFunction.

Returns:PartialFunction<T1, R>

a new PartialFunction that has the same behavior like this function but is defined only for those elements that make it through the given Predicate

Exceptions

NullPointerException:: if isDefinedAt is null

reversed	back to summary
public default Function1<T1, R> reversed() Returns a reversed version of this function. This may be useful in a recursive context. Returns:Function1<T1, R> a reversed function equivalent to this.

reversed

back to summary

public default Function1<T1, R> reversed()

Returns a reversed version of this function. This may be useful in a recursive context.

Returns:Function1<T1, R>: a reversed function equivalent to this.

tupled	back to summary
public default Function1<Tuple1<T1>, R> tupled() Returns a tupled version of this function. Returns:Function1<Tuple1<T1>, R> a tupled function equivalent to this.

tupled

back to summary

public default Function1<Tuple1<T1>, R> tupled()

Returns a tupled version of this function.

Returns:Function1<Tuple1<T1>, R>: a tupled function equivalent to this.

public Interface Function1<T1, R>

Field Summary

Method Summary

Field Detail

Method Detail