Higher Order Functions Hall of Fame Assignment

Code To Implement

Higher-order Functions

class:	Hof.java
methods:	filter foldLeft foldRight map find
package:	hof.util.exercise
source folder:	src/main/java

filter

SML List filter

public static <E> ImList<E> filter(Predicate<E> predicate, ImList<E> list)

foldLeft

SML List foldl

foldLeft(f, initial_value, [x1, x2, ..., xn])

returns f(xn,...,f(x2, f(x1, initial_value))...) or initial_value if the list is empty.

public static <E, R> R foldLeft(BiFunction<E, R, R> f, R acc, ImList<E> list)

foldRight

SML List foldr

foldRight(f, initial_value, [x1, x2, ..., xn])

returns f(x1, f(x2, ..., f(xn, init)...)) or initial_value if the list is empty.

public static <E, R> R foldRight(BiFunction<E, R, R> f, R acc, ImList<E> list)

map

SML List map

public static <E, R> ImList<R> map(Function<E, R> f, ImList<E> list)

find

SML List map

public static <E> Optional<E> find(Predicate<E> predicate, ImList<E> list)

Clients

class:	HofClients.java
methods:	filterWordsWhichContainAllVowels filterEvens sum countBetweenMinAndMaxExclusive mapToLengths mapToStrictlyLessThan findFirstPalindrome
package:	hof.clients.exercise
source folder:	src/main/java

public static ImmutableList<String> filterWordsWhichContainAllVowels(ImmutableList<String> words)

public static ImmutableList<Integer> filterEvens(ImmutableList<Integer> xs)

sum

public static int sum(ImmutableList<Integer> xs)

countBetweenMinAndMaxExclusive

public static int countBetweenMinAndMaxExclusive(int min, int maxExclusive, ImmutableList<Integer> xs)

mapToLengths

public static ImmutableList<Integer> mapToLengths(ImmutableList<String> texts)

Use the String class's length() method.

mapToStrictlyLessThan

public static ImmutableList<Boolean> mapToStrictlyLessThan(ImmutableList<Integer> xs, int threshold)

findFirstPalindrome

public static Optional<String> findFirstPalindrome(ImmutableList<String> words)

Test

class:	HigherOrderFunctionTestSuite.java
package:	hof
source folder:	src/test/java