Interface Seq<T>

Type Parameters:
T - Component type
All Superinterfaces:
Foldable<T>, Function<Integer,T>, Function1<Integer,T>, Iterable<T>, PartialFunction<Integer,T>, Serializable, Traversable<T>, Value<T>
All Known Subinterfaces:
IndexedSeq<T>, LinearSeq<T>, List<T>, Stream<T>
All Known Implementing Classes:
Array, CharSeq, List.Cons, List.Nil, Queue, Stream.Cons, Stream.Empty, Vector

public interface Seq<T> extends Traversable<T>, PartialFunction<Integer,T>, Serializable
Author:
Daniel Dietrich
  • Field Details

  • Method Details

    • narrow

      static <T> Seq<T> narrow(Seq<? extends T> seq)
      Narrows a widened Seq<? extends T> to Seq<T> by performing a type-safe cast. This is eligible because immutable/read-only collections are covariant.
      Type Parameters:
      T - Component type of the Seq.
      Parameters:
      seq - A Seq.
      Returns:
      the given seq instance as narrowed type Seq<T>.
    • append

      Seq<T> append(T element)
      Appends an element to this.
      Parameters:
      element - An element
      Returns:
      A new Seq containing the given element appended to this elements
    • appendAll

      Seq<T> appendAll(Iterable<? extends T> elements)
      Appends all given elements to this.
      Parameters:
      elements - An Iterable of elements
      Returns:
      A new Seq containing the given elements appended to this elements
      Throws:
      NullPointerException - if elements is null
    • apply

      @Deprecated default T apply(Integer index)
      Deprecated.
      Will be removed
      A Seq is a partial function which returns the element at the specified index by calling get(int).
      Specified by:
      apply in interface Function<Integer,T>
      Specified by:
      apply in interface Function1<Integer,T>
      Specified by:
      apply in interface PartialFunction<Integer,T>
      Parameters:
      index - an index
      Returns:
      the element at the given index
      Throws:
      IndexOutOfBoundsException - if this is empty, index < 0 or index >= length()
    • asJava

      @GwtIncompatible List<T> asJava()
      Creates an immutable List view on top of this Seq, i.e. calling mutators will result in UnsupportedOperationException at runtime.

      The difference to conversion methods toJava*() is that

      • A view is created in O(1) (constant time) whereas conversion takes O(n) (linear time), with n = collection size.
      • The operations on a view have the same performance characteristics than the underlying persistent Vavr collection whereas the performance characteristics of a converted collection are those of the Java standard collections.
      Please note that our immutable java.util.List view throws UnsupportedOperationException before checking method arguments. Java does handle this case inconsistently.
      Returns:
      A new immutable Collection view on this Traversable.
    • asJava

      @GwtIncompatible Seq<T> asJava(Consumer<? super List<T>> action)
      Creates an immutable List view on top of this Seq that is passed to the given action.
      Parameters:
      action - A side-effecting unit of work that operates on an immutable java.util.List view.
      Returns:
      this instance
      See Also:
    • asJavaMutable

      @GwtIncompatible List<T> asJavaMutable()
      Creates a mutable List view on top of this Seq, i.e. all mutator methods of the List are implemented.
      Returns:
      A new mutable Collection view on this Traversable.
      See Also:
    • asJavaMutable

      @GwtIncompatible Seq<T> asJavaMutable(Consumer<? super List<T>> action)
      Creates a mutable List view on top of this Seq that is passed to the given action.
      Parameters:
      action - A side-effecting unit of work that operates on a mutable java.util.List view.
      Returns:
      this instance, if only read operations are performed on the java.util.List view or a new instance of this type, if write operations are performed on the java.util.List view.
      See Also:
    • asPartialFunction

      PartialFunction<Integer,T> asPartialFunction() throws IndexOutOfBoundsException
      Turns this Seq into a PartialFunction which is defined at a specific index, if this Seq contains at least index + 1 elements. When applied to a defined index, the partial function will return the value of this Seq at the specified index.
      Returns:
      a new PartialFunction
      Throws:
      IndexOutOfBoundsException - if this is empty, index < 0 or index >= length()
    • collect

      <R> Seq<R> collect(PartialFunction<? super T,? extends R> partialFunction)
      Description copied from interface: Traversable
      Collects all elements that are in the domain of the given partialFunction by mapping the elements to type R.

      More specifically, for each of this elements in iteration order first it is checked

      
       partialFunction.isDefinedAt(element)
       
      If the elements makes it through that filter, the mapped instance is added to the result collection
      
       R newElement = partialFunction.apply(element)
       
      Note:If this Traversable is ordered (i.e. extends Ordered, the caller of collect has to ensure that the elements are comparable (i.e. extend Comparable).
      Specified by:
      collect in interface Traversable<T>
      Type Parameters:
      R - The new element type
      Parameters:
      partialFunction - A function that is not necessarily defined of all elements of this traversable.
      Returns:
      A new Traversable instance containing elements of type R
    • combinations

      Seq<? extends Seq<T>> combinations()
      Returns the union of all combinations from k = 0 to length().

      Examples:

       
       [].combinations() = [[]]
      
       [1,2,3].combinations() = [
         [],                  // k = 0
         [1], [2], [3],       // k = 1
         [1,2], [1,3], [2,3], // k = 2
         [1,2,3]              // k = 3
       ]
       
       
      Returns:
      the combinations of this
    • combinations

      Seq<? extends Seq<T>> combinations(int k)
      Returns the k-combination of this traversable, i.e. all subset of this of k distinct elements.
      Parameters:
      k - Size of subsets
      Returns:
      the k-combination of this elements
      See Also:
    • containsSlice

      default boolean containsSlice(Iterable<? extends T> that)
      Tests whether this sequence contains a given sequence as a slice.

      Note: may not terminate for infinite sequences.

      Parameters:
      that - the sequence to test
      Returns:
      true if this sequence contains a slice with the same elements as that, otherwise false.
      Throws:
      NullPointerException - if that is null.
    • crossProduct

      default Iterator<Tuple2<T,T>> crossProduct()
      Calculates the cross product (, i.e. square) of this x this.

      Example:

       
       // = List of Tuples (1, 1), (1, 2), (1, 3), (2, 1), (2, 2), (2, 3), (3, 1), (3, 2), (3, 3)
       List.of(1, 2, 3).crossProduct();
       
       
      Returns:
      a new Iterator containing the square of this
    • crossProduct

      Iterator<? extends Seq<T>> crossProduct(int power)
      Calculates the n-ary cartesian power (or cross product or simply product) of this.

      Example:

       
       // = ((A,A), (A,B), (A,C), ..., (B,A), (B,B), ..., (Z,Y), (Z,Z))
       CharSeq.rangeClosed('A', 'Z').crossProduct(2);
       
       

      Cartesian power of negative value will return empty iterator.

      Example:

       
       // = ()
       CharSeq.rangeClosed('A', 'Z').crossProduct(-1);
       
       
      Parameters:
      power - the number of cartesian multiplications
      Returns:
      A new Iterator representing the n-ary cartesian power of this
    • crossProduct

      default <U> Iterator<Tuple2<T,U>> crossProduct(Iterable<? extends U> that)
      Calculates the cross product this x that.

      Example:

       
       // = List of Tuples (1, 'a'), (1, 'b'), (2, 'a'), (2, 'b'), (3, 'a'), (3, 'b')
       List.of(1, 2, 3).crossProduct(List.of('a', 'b');
       
       
      Type Parameters:
      U - Component type
      Parameters:
      that - Another iterable
      Returns:
      a new Iterator containing the cross product this x that
      Throws:
      NullPointerException - if that is null
    • endsWith

      default boolean endsWith(Seq<? extends T> that)
      Tests whether this sequence ends with the given sequence.

      Note: If the both the receiver object this and the argument that are infinite sequences this method may not terminate.

      Parameters:
      that - the sequence to test
      Returns:
      true if this sequence has that as a suffix, false otherwise.
    • get

      T get(int index)
      Returns the element at the specified index.
      Parameters:
      index - an index
      Returns:
      the element at the given index
      Throws:
      IndexOutOfBoundsException - if this is empty, index < 0 or index >= length()
    • indexOf

      default int indexOf(T element)
      Returns the index of the first occurrence of the given element or -1 if this does not contain the given element.
      Parameters:
      element - an element
      Returns:
      the index of the first occurrence of the given element
    • indexOfOption

      default Option<Integer> indexOfOption(T element)
      Returns the index of the first occurrence of the given element as an Option
      Parameters:
      element - an element
      Returns:
      Some(index) or None if not found.
    • indexOf

      int indexOf(T element, int from)
      Returns the index of the first occurrence of the given element after or at some start index or -1 if this does not contain the given element.
      Parameters:
      element - an element
      from - start index
      Returns:
      the index of the first occurrence of the given element
    • indexOfOption

      default Option<Integer> indexOfOption(T element, int from)
      Returns the index of the first occurrence of the given element, after or at some start index as an Option
      Parameters:
      element - an element
      from - start index
      Returns:
      Some(index) or None if not found.
    • indexOfSlice

      default int indexOfSlice(Iterable<? extends T> that)
      Finds first index where this sequence contains a given sequence as a slice.

      Note: may not terminate for infinite sequences.

      Parameters:
      that - the sequence to test
      Returns:
      the first index such that the elements of this sequence starting at this index match the elements of sequence that, or -1 of no such slice exists.
      Throws:
      NullPointerException - if that is null.
    • indexOfSliceOption

      default Option<Integer> indexOfSliceOption(Iterable<? extends T> that)
      Finds first index where this sequence contains a given sequence as an Option of a slice.

      Note: may not terminate for infinite sequences.

      Parameters:
      that - the sequence to test
      Returns:
      Some(index) or None if not found.
    • indexOfSlice

      int indexOfSlice(Iterable<? extends T> that, int from)
      Finds first index after or at a start index where this sequence contains a given sequence as a slice. Note: may not terminate for infinite sequences.
      Parameters:
      that - the sequence to test
      from - the start index
      Returns:
      the first index >= from such that the elements of this sequence starting at this index match the elements of sequence that, or -1 of no such slice exists.
      Throws:
      NullPointerException - if that is null.
    • indexOfSliceOption

      default Option<Integer> indexOfSliceOption(Iterable<? extends T> that, int from)
      Finds first index after or at a start index where this sequence contains a given sequence as an Option of a slice. Note: may not terminate for infinite sequences.
      Parameters:
      that - the sequence to test
      from - the start index
      Returns:
      Some(index) or None if not found.
    • indexWhere

      default int indexWhere(Predicate<? super T> predicate)
      Finds index of first element satisfying some predicate.
      Parameters:
      predicate - the predicate used to test elements.
      Returns:
      the index of the first element of this Seq that satisfies the given predicate, or -1, if none exists.
    • indexWhereOption

      default Option<Integer> indexWhereOption(Predicate<? super T> predicate)
      Finds index of first element satisfying some predicate as an Option.
      Parameters:
      predicate - the predicate used to test elements.
      Returns:
      Some(index) or None if not found.
    • indexWhere

      int indexWhere(Predicate<? super T> predicate, int from)
      Finds index of the first element satisfying some predicate after or at some start index.
      Parameters:
      predicate - the predicate used to test elements.
      from - the start index
      Returns:
      the index >= from of the first element of this Seq that satisfies the given predicate, or -1, if none exists.
    • indexWhereOption

      default Option<Integer> indexWhereOption(Predicate<? super T> predicate, int from)
      Finds index of the first element satisfying some predicate after or at some start index as an Option.
      Parameters:
      predicate - the predicate used to test elements.
      from - the start index
      Returns:
      Some(index) or None if not found.
    • insert

      Seq<T> insert(int index, T element)
      Inserts the given element at the specified index.
      Parameters:
      index - an index
      element - an element
      Returns:
      a new Seq, where the given element is inserted into this at the given index
      Throws:
      IndexOutOfBoundsException - if this is empty, index < 0 or index >= length()
    • insertAll

      Seq<T> insertAll(int index, Iterable<? extends T> elements)
      Inserts the given elements at the specified index.
      Parameters:
      index - an index
      elements - An Iterable of elements
      Returns:
      a new Seq, where the given elements are inserted into this at the given index
      Throws:
      IndexOutOfBoundsException - if this is empty, index < 0 or index >= length()
    • intersperse

      Seq<T> intersperse(T element)
      Inserts an element between all elements of this Traversable.
      Parameters:
      element - An element.
      Returns:
      an interspersed version of this
    • iterator

      default Iterator<T> iterator(int index)
      Returns an iterator of this elements starting at the given index. The result is equivalent to this.subSequence(index).iterator().
      Parameters:
      index - an index
      Returns:
      a new Iterator, starting with the element at the given index or the empty Iterator, if index = length()
      Throws:
      IndexOutOfBoundsException - if index < 0 or index > length()
    • lastIndexOf

      default int lastIndexOf(T element)
      Returns the index of the last occurrence of the given element or -1 if this does not contain the given element.
      Parameters:
      element - an element
      Returns:
      the index of the last occurrence of the given element
    • lastIndexOfOption

      default Option<Integer> lastIndexOfOption(T element)
      Returns the index of the last occurrence of the given element as an Option.
      Parameters:
      element - an element
      Returns:
      Some(index) or None if not found.
    • lastIndexWhere

      default int lastIndexWhere(Predicate<? super T> predicate)
      Finds index of last element satisfying some predicate.
      Parameters:
      predicate - the predicate used to test elements.
      Returns:
      the index of the last element of this Seq that satisfies the given predicate, or -1, if none exists.
    • lastIndexWhereOption

      default Option<Integer> lastIndexWhereOption(Predicate<? super T> predicate)
      Finds index of last element satisfying some predicate as an Option.
      Parameters:
      predicate - the predicate used to test elements.
      Returns:
      Some(index) or None if not found.
    • lastIndexWhere

      int lastIndexWhere(Predicate<? super T> predicate, int end)
      Finds index of last element satisfying some predicate before or at given end index.
      Parameters:
      predicate - the predicate used to test elements.
      end - the maximum index of the search
      Returns:
      the index <= end of the last element of this Seq that satisfies the given predicate, or -1, if none exists.
    • lastIndexWhereOption

      default Option<Integer> lastIndexWhereOption(Predicate<? super T> predicate, int end)
      Finds index of last element satisfying some predicate before or at given end index as an Option.
      Parameters:
      predicate - the predicate used to test elements.
      end - the maximum index of the search
      Returns:
      Some(index) or None if not found.
    • lift

      @Deprecated default Function1<Integer,Option<T>> lift()
      Deprecated.
      Will be removed
      Turns this sequence into a plain function returning an Option result.
      Specified by:
      lift in interface PartialFunction<Integer,T>
      Returns:
      a function that takes an index i and returns the value of this sequence in a Some if the index is within bounds, otherwise a None.
    • lastIndexOf

      int lastIndexOf(T element, int end)
      Returns the index of the last occurrence of the given element before or at a given end index or -1 if this does not contain the given element.
      Parameters:
      element - an element
      end - the end index
      Returns:
      the index of the last occurrence of the given element
    • lastIndexOfOption

      default Option<Integer> lastIndexOfOption(T element, int end)
      Returns the index of the last occurrence of the given element before or at a given end index as an Option.
      Parameters:
      element - an element
      end - the end index
      Returns:
      Some(index) or None if not found.
    • lastIndexOfSlice

      default int lastIndexOfSlice(Iterable<? extends T> that)
      Finds last index where this sequence contains a given sequence as a slice.

      Note: will not terminate for infinite sequences.

      Parameters:
      that - the sequence to test
      Returns:
      the last index such that the elements of this sequence starting a this index match the elements of sequence that, or -1 of no such slice exists.
      Throws:
      NullPointerException - if that is null.
    • lastIndexOfSliceOption

      default Option<Integer> lastIndexOfSliceOption(Iterable<? extends T> that)
      Finds last index where this sequence contains a given sequence as a slice as an Option.
      Parameters:
      that - the sequence to test
      Returns:
      Some(index) or None if not found.
    • lastIndexOfSlice

      int lastIndexOfSlice(Iterable<? extends T> that, int end)
      Finds last index before or at a given end index where this sequence contains a given sequence as a slice.
      Parameters:
      that - the sequence to test
      end - the end index
      Returns:
      the last index <= end such that the elements of this sequence starting at this index match the elements of sequence that, or -1 of no such slice exists.
      Throws:
      NullPointerException - if that is null.
    • lastIndexOfSliceOption

      default Option<Integer> lastIndexOfSliceOption(Iterable<? extends T> that, int end)
      Finds last index before or at a given end index where this sequence contains a given sequence as a slice as an Option.
      Parameters:
      that - the sequence to test
      end - the end index
      Returns:
      Some(index) or None if not found.
    • padTo

      Seq<T> padTo(int length, T element)
      A copy of this sequence with an element appended until a given target length is reached.

      Note: lazily-evaluated Seq implementations need to process all elements in order to gather the overall length.

      Parameters:
      length - the target length
      element - the padding element
      Returns:
      a new sequence consisting of all elements of this sequence followed by the minimal number of occurrences of element so that the resulting sequence has a length of at least length.
    • leftPadTo

      Seq<T> leftPadTo(int length, T element)
      A copy of this sequence with an element prepended until a given target length is reached.

      Note: lazily-evaluated Seq implementations need to process all elements in order to gather the overall length.

      Parameters:
      length - the target length
      element - the padding element
      Returns:
      a new sequence consisting of all elements of this sequence prepended by the minimal number of occurrences of element so that the resulting sequence has a length of at least length.
    • patch

      Seq<T> patch(int from, Iterable<? extends T> that, int replaced)
      Produces a new list where a slice of elements in this list is replaced by another sequence.
      Parameters:
      from - the index of the first replaced element
      that - sequence for replacement
      replaced - the number of elements to drop in the original list
      Returns:
      a new sequence.
    • permutations

      Seq<? extends Seq<T>> permutations()
      Computes all unique permutations.

      Example:

       
       [].permutations() = []
      
       [1,2,3].permutations() = [
         [1,2,3],
         [1,3,2],
         [2,1,3],
         [2,3,1],
         [3,1,2],
         [3,2,1]
       ]
       
       
      Returns:
      this unique permutations
    • prefixLength

      default int prefixLength(Predicate<? super T> predicate)
      Returns the length of the longest prefix whose elements all satisfy some predicate. Note: may not terminate for infinite-sized collections.
      Parameters:
      predicate - the predicate used to test elements.
      Returns:
      the length of the longest prefix of this general sequence such that every element of the segment satisfies the predicate p.
    • prepend

      Seq<T> prepend(T element)
      Prepends an element to this.
      Parameters:
      element - An element
      Returns:
      A new Seq containing the given element prepended to this elements
    • prependAll

      Seq<T> prependAll(Iterable<? extends T> elements)
      Prepends all given elements to this.
      Parameters:
      elements - An Iterable of elements
      Returns:
      A new Seq containing the given elements prepended to this elements
    • remove

      Seq<T> remove(T element)
      Removes the first occurrence of the given element.
      Parameters:
      element - An element to be removed from this Seq.
      Returns:
      a Seq containing all elements of this without the first occurrence of the given element.
    • removeAll

      Seq<T> removeAll(T element)
      Removes all occurrences of the given element.
      Parameters:
      element - An element to be removed from this Seq.
      Returns:
      a Seq containing all elements of this but not the given element.
    • removeAll

      Seq<T> removeAll(Iterable<? extends T> elements)
      Removes all occurrences of the given elements.
      Parameters:
      elements - Elements to be removed from this Seq.
      Returns:
      a Seq containing all elements of this but none of the given elements.
      Throws:
      NullPointerException - if elements is null
    • removeAll

      @Deprecated Seq<T> removeAll(Predicate<? super T> predicate)
      Deprecated.
      Returns a new Seq consisting of all elements which do not satisfy the given predicate.
      Parameters:
      predicate - the predicate used to test elements
      Returns:
      a new Seq
      Throws:
      NullPointerException - if predicate is null
    • removeAt

      Seq<T> removeAt(int index)
      Removes the element at the specified position in this sequence. Shifts any subsequent elements to the left (subtracts one from their indices).
      Parameters:
      index - position of element to remove
      Returns:
      a sequence containing all elements of this without the element at the specified position.
      Throws:
      IndexOutOfBoundsException - if this is empty, index < 0 or index >= length()
    • removeFirst

      Seq<T> removeFirst(Predicate<T> predicate)
      Removes the first occurrence that satisfy predicate
      Parameters:
      predicate - an predicate
      Returns:
      a new Seq
    • removeLast

      Seq<T> removeLast(Predicate<T> predicate)
      Removes the last occurrence that satisfy predicate
      Parameters:
      predicate - an predicate
      Returns:
      a new Seq
    • reverse

      Seq<T> reverse()
      Reverses the order of elements.
      Returns:
      the reversed elements.
    • reverseIterator

      Iterator<T> reverseIterator()
      An iterator yielding elements in reversed order.

      Note: xs.reverseIterator() is the same as xs.reverse().iterator() but might be more efficient.

      Returns:
      an iterator yielding the elements of this Seq in reversed order
    • rotateLeft

      Seq<T> rotateLeft(int n)
      Circular rotates the elements by the specified distance to the left direction.
      
       // = List(3, 4, 5, 1, 2)
       List.of(1, 2, 3, 4, 5).rotateLeft(2);
       
      Parameters:
      n - distance of left rotation
      Returns:
      the rotated elements.
    • rotateRight

      Seq<T> rotateRight(int n)
      Circular rotates the elements by the specified distance to the right direction.
      
       // = List(4, 5, 1, 2, 3)
       List.of(1, 2, 3, 4, 5).rotateRight(2);
       
      Parameters:
      n - distance of right rotation
      Returns:
      the rotated elements.
    • segmentLength

      int segmentLength(Predicate<? super T> predicate, int from)
      Computes length of longest segment whose elements all satisfy some predicate.

      Note: may not terminate for infinite sequences.

      Parameters:
      predicate - the predicate used to test elements.
      from - the index where the search starts.
      Returns:
      the length of the longest segment of this sequence starting from index from such that every element of the segment satisfies the predicate p.
    • shuffle

      Seq<T> shuffle()
      Randomize the order of the elements in the current sequence.
      Returns:
      a sequence with the same elements as the current sequence in a random order.
    • slice

      Seq<T> slice(int beginIndex, int endIndex)
      Returns a Seq that is a slice of this. The slice begins with the element at the specified beginIndex and extends to the element at index endIndex - 1.

      Examples:

       
       List.of(1, 2, 3, 4).slice(1, 3); // = (2, 3)
       List.of(1, 2, 3, 4).slice(0, 4); // = (1, 2, 3, 4)
       List.of(1, 2, 3, 4).slice(2, 2); // = ()
       List.of(1, 2).slice(1, 0);       // = ()
       List.of(1, 2).slice(-10, 10);    // = (1, 2)
       
       
      See also subSequence(int, int) which throws in some cases instead of returning a sequence.
      Parameters:
      beginIndex - the beginning index, inclusive
      endIndex - the end index, exclusive
      Returns:
      the specified slice
    • sorted

      Seq<T> sorted()
      Sorts this elements according to their natural order. If this elements are not Comparable, a java.lang.ClassCastException may be thrown.
      Returns:
      A sorted version of this
      Throws:
      ClassCastException - if this elements are not Comparable
    • sorted

      Seq<T> sorted(Comparator<? super T> comparator)
      Sorts this elements according to the provided Comparator. If this elements are not Comparable, a java.lang.ClassCastException may be thrown.
      Parameters:
      comparator - A comparator
      Returns:
      a sorted version of this
    • sortBy

      <U extends Comparable<? super U>> Seq<T> sortBy(Function<? super T,? extends U> mapper)
      Sorts this elements by comparing the elements in a different domain, using the given mapper.
      Type Parameters:
      U - The domain where elements are compared
      Parameters:
      mapper - A mapper
      Returns:
      a sorted version of this
      Throws:
      NullPointerException - if mapper is null
    • sortBy

      <U> Seq<T> sortBy(Comparator<? super U> comparator, Function<? super T,? extends U> mapper)
      Sorts this elements by comparing the elements in a different domain, using the given mapper.
      Type Parameters:
      U - The domain where elements are compared
      Parameters:
      comparator - A comparator
      mapper - A mapper
      Returns:
      a sorted version of this
      Throws:
      NullPointerException - if comparator or mapper is null
    • splitAt

      Tuple2<? extends Seq<T>,? extends Seq<T>> splitAt(int n)
      Splits a Seq at the specified index. The result of splitAt(n) is equivalent to Tuple.of(take(n), drop(n)).
      Parameters:
      n - An index.
      Returns:
      A Tuple containing the first n and the remaining elements.
    • splitAt

      Tuple2<? extends Seq<T>,? extends Seq<T>> splitAt(Predicate<? super T> predicate)
      Splits a sequence at the first element which satisfies the Predicate, e.g. Tuple(init, element+tail).
      Parameters:
      predicate - An predicate
      Returns:
      A Tuple containing divided sequences
    • splitAtInclusive

      Tuple2<? extends Seq<T>,? extends Seq<T>> splitAtInclusive(Predicate<? super T> predicate)
      Splits a sequence at the first element which satisfies the Predicate, e.g. Tuple(init+element, tail).
      Parameters:
      predicate - An predicate
      Returns:
      A Tuple containing divided sequences
    • startsWith

      default boolean startsWith(Iterable<? extends T> that)
      Tests whether this list starts with the given sequence.
      Parameters:
      that - the sequence to test
      Returns:
      true if that is empty or that is prefix of this collection, false otherwise.
    • startsWith

      default boolean startsWith(Iterable<? extends T> that, int offset)
      Tests whether this list contains the given sequence at a given index.

      Note: If the both the receiver object this and the argument that are infinite sequences this method may not terminate.

      Parameters:
      that - the sequence to test
      offset - the index where the sequence is searched.
      Returns:
      true if that is empty or that is prefix of this collection starting from the given offset, false otherwise.
    • subSequence

      Seq<T> subSequence(int beginIndex)
      Returns a Seq that is a subsequence of this. The subsequence begins with the element at the specified beginIndex and extends to the end of this Seq.

      Examples:

       
       List.of(1, 2).subSequence(0);     // = (1, 2)
       List.of(1, 2).subSequence(1);     // = (2)
       List.of(1, 2).subSequence(2);     // = ()
       List.of(1, 2).subSequence(10);    // throws IndexOutOfBoundsException
       List.of(1, 2).subSequence(-10);   // throws IndexOutOfBoundsException
       
       
      See also drop(int) which is similar but does not throw.
      Parameters:
      beginIndex - the beginning index, inclusive
      Returns:
      the specified subsequence
      Throws:
      IndexOutOfBoundsException - if beginIndex is negative or larger than the length of this String object.
    • subSequence

      Seq<T> subSequence(int beginIndex, int endIndex)
      Returns a Seq that is a subsequence of this. The subsequence begins with the element at the specified beginIndex and extends to the element at index endIndex - 1.

      Examples:

       
       List.of(1, 2, 3, 4).subSequence(1, 3); // = (2, 3)
       List.of(1, 2, 3, 4).subSequence(0, 4); // = (1, 2, 3, 4)
       List.of(1, 2, 3, 4).subSequence(2, 2); // = ()
       List.of(1, 2).subSequence(1, 0);       // throws IndexOutOfBoundsException
       List.of(1, 2).subSequence(-10, 1);     // throws IndexOutOfBoundsException
       List.of(1, 2).subSequence(0, 10);      // throws IndexOutOfBoundsException
       
       
      See also slice(int, int) which returns an empty sequence instead of throwing.
      Parameters:
      beginIndex - the beginning index, inclusive
      endIndex - the end index, exclusive
      Returns:
      the specified subsequence
      Throws:
      IndexOutOfBoundsException - if beginIndex or endIndex is negative or if endIndex is greater than length()
      IllegalArgumentException - if beginIndex is greater than endIndex
    • update

      Seq<T> update(int index, T element)
      Updates the given element at the specified index.
      Parameters:
      index - an index
      element - an element
      Returns:
      a new Seq consisting of all previous elements, with a single one (at the given index), changed to the new value.
      Throws:
      IndexOutOfBoundsException - if this is empty, index < 0 or index >= length()
    • update

      Seq<T> update(int index, Function<? super T,? extends T> updater)
      Updates the given element at the specified index using the specified function.
      Parameters:
      index - an index
      updater - a function transforming the previous value
      Returns:
      a new Seq consisting of all previous elements, with a single one (at the given index), changed to the new value.
      Throws:
      IndexOutOfBoundsException - if this is empty, index < 0 or index >= length()
    • search

      int search(T element)
      Searches this sequence for a specific element. The sequence must already be sorted into ascending natural order. If it is not sorted, the results are undefined.

      If this sequence is an `IndexedSeq`, a binary search is used. Otherwise, a linear search is used.

      Parameters:
      element - the element to find
      Returns:
      the index of the search element, if it is contained in the sequence; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the element would be inserted into the sequence. Note that this guarantees that the return value will be >= 0 if and only if the element is found.
      Throws:
      ClassCastException - if T cannot be cast to Comparable<? super T>
    • search

      int search(T element, Comparator<? super T> comparator)
      Searches this sequence for a specific element. The sequence must already be sorted into ascending order according to the specified comparator. If it is not sorted, the results are undefined.

      If this sequence is an `IndexedSeq`, a binary search is used. Otherwise, a linear search is used.

      Parameters:
      element - the element to find
      comparator - the comparator by which this sequence is ordered
      Returns:
      the index of the search element, if it is contained in the sequence; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the element would be inserted into the sequence. Note that this guarantees that the return value will be >= 0 if and only if the element is found.
    • distinct

      Seq<T> distinct()
      Description copied from interface: Traversable
      Returns a new version of this which contains no duplicates. Elements are compared using equals.
      Specified by:
      distinct in interface Traversable<T>
      Returns:
      a new Traversable containing this elements without duplicates
    • distinctBy

      Seq<T> distinctBy(Comparator<? super T> comparator)
      Description copied from interface: Traversable
      Returns a new version of this which contains no duplicates. Elements are compared using the given comparator.
      Specified by:
      distinctBy in interface Traversable<T>
      Parameters:
      comparator - A comparator
      Returns:
      a new Traversable containing this elements without duplicates
    • distinctBy

      <U> Seq<T> distinctBy(Function<? super T,? extends U> keyExtractor)
      Description copied from interface: Traversable
      Returns a new version of this which contains no duplicates. Elements mapped to keys which are compared using equals.

      The elements of the result are determined in the order of their occurrence - first match wins.

      Specified by:
      distinctBy in interface Traversable<T>
      Type Parameters:
      U - key type
      Parameters:
      keyExtractor - A key extractor
      Returns:
      a new Traversable containing this elements without duplicates
    • drop

      Seq<T> drop(int n)
      Description copied from interface: Traversable
      Drops the first n elements of this or all elements, if this length < n.
      Specified by:
      drop in interface Traversable<T>
      Parameters:
      n - The number of elements to drop.
      Returns:
      a new instance consisting of all elements of this except the first n ones, or else the empty instance, if this has less than n elements.
    • dropUntil

      Seq<T> dropUntil(Predicate<? super T> predicate)
      Description copied from interface: Traversable
      Drops elements until the predicate holds for the current element.
      Specified by:
      dropUntil in interface Traversable<T>
      Parameters:
      predicate - A condition tested subsequently for this elements.
      Returns:
      a new instance consisting of all elements starting from the first one which does satisfy the given predicate.
    • dropWhile

      Seq<T> dropWhile(Predicate<? super T> predicate)
      Description copied from interface: Traversable
      Drops elements while the predicate holds for the current element.

      Note: This is essentially the same as dropUntil(predicate.negate()). It is intended to be used with method references, which cannot be negated directly.

      Specified by:
      dropWhile in interface Traversable<T>
      Parameters:
      predicate - A condition tested subsequently for this elements.
      Returns:
      a new instance consisting of all elements starting from the first one which does not satisfy the given predicate.
    • dropRight

      Seq<T> dropRight(int n)
      Description copied from interface: Traversable
      Drops the last n elements of this or all elements, if this length < n.
      Specified by:
      dropRight in interface Traversable<T>
      Parameters:
      n - The number of elements to drop.
      Returns:
      a new instance consisting of all elements of this except the last n ones, or else the empty instance, if this has less than n elements.
    • dropRightUntil

      Seq<T> dropRightUntil(Predicate<? super T> predicate)
      Drops elements until the predicate holds for the current element, starting from the end.
      Parameters:
      predicate - A condition tested subsequently for this elements, starting from the end.
      Returns:
      a new instance consisting of all elements until and including the last one which does satisfy the given predicate.
      Throws:
      NullPointerException - if predicate is null
    • dropRightWhile

      Seq<T> dropRightWhile(Predicate<? super T> predicate)
      Drops elements while the predicate holds for the current element, starting from the end.

      Note: This is essentially the same as dropRightUntil(predicate.negate()). It is intended to be used with method references, which cannot be negated directly.

      Parameters:
      predicate - A condition tested subsequently for this elements, starting from the end.
      Returns:
      a new instance consisting of all elements until and including the last one which does not satisfy the given predicate.
      Throws:
      NullPointerException - if predicate is null
    • filter

      Seq<T> filter(Predicate<? super T> predicate)
      Description copied from interface: Traversable
      Returns a new traversable consisting of all elements which satisfy the given predicate.
      Specified by:
      filter in interface Traversable<T>
      Parameters:
      predicate - A predicate
      Returns:
      a new traversable
    • reject

      Seq<T> reject(Predicate<? super T> predicate)
      Description copied from interface: Traversable
      Returns a new traversable consisting of all elements which do not satisfy the given predicate.

      The default implementation is equivalent to

      filter(predicate.negate()
      Specified by:
      reject in interface Traversable<T>
      Parameters:
      predicate - A predicate
      Returns:
      a new traversable
    • flatMap

      <U> Seq<U> flatMap(Function<? super T,? extends Iterable<? extends U>> mapper)
      Description copied from interface: Traversable
      FlatMaps this Traversable.
      Specified by:
      flatMap in interface Traversable<T>
      Type Parameters:
      U - The resulting component type.
      Parameters:
      mapper - A mapper
      Returns:
      A new Traversable instance.
    • foldRight

      default <U> U foldRight(U zero, BiFunction<? super T,? super U,? extends U> f)
      Description copied from interface: Foldable
      Folds this elements from the right, starting with zero and successively calling combine.

      Example:

       
       // = "!cba"
       List("a", "b", "c").foldRight("!", (x, xs) -> xs + x)
        
      Specified by:
      foldRight in interface Foldable<T>
      Specified by:
      foldRight in interface Traversable<T>
      Type Parameters:
      U - the type of the folded value
      Parameters:
      zero - A zero element to start with.
      f - A function which combines elements.
      Returns:
      a folded value
    • groupBy

      <C> Map<C,? extends Seq<T>> groupBy(Function<? super T,? extends C> classifier)
      Description copied from interface: Traversable
      Groups this elements by classifying the elements.
      Specified by:
      groupBy in interface Traversable<T>
      Type Parameters:
      C - classified class type
      Parameters:
      classifier - A function which classifies elements into classes
      Returns:
      A Map containing the grouped elements
      See Also:
    • grouped

      Iterator<? extends Seq<T>> grouped(int size)
      Description copied from interface: Traversable
      Groups this Traversable into fixed size blocks.

      Let length be the length of this Iterable. Then grouped is defined as follows:

      • If this.isEmpty(), the resulting Iterator is empty.
      • If size <= length, the resulting Iterator will contain length / size blocks of size size and maybe a non-empty block of size length % size, if there are remaining elements.
      • If size > length, the resulting Iterator will contain one block of size length.
      Examples:
       
       [].grouped(1) = []
       [].grouped(0) throws
       [].grouped(-1) throws
       [1,2,3,4].grouped(2) = [[1,2],[3,4]]
       [1,2,3,4,5].grouped(2) = [[1,2],[3,4],[5]]
       [1,2,3,4].grouped(5) = [[1,2,3,4]]
       
       
      Please note that grouped(int) is a special case of Traversable.sliding(int, int), i.e. grouped(size) is the same as sliding(size, size).
      Specified by:
      grouped in interface Traversable<T>
      Parameters:
      size - a positive block size
      Returns:
      A new Iterator of grouped blocks of the given size
    • init

      Seq<T> init()
      Description copied from interface: Traversable
      Dual of Traversable.tail(), returning all elements except the last.
      Specified by:
      init in interface Traversable<T>
      Returns:
      a new instance containing all elements except the last.
    • initOption

      Option<? extends Seq<T>> initOption()
      Description copied from interface: Traversable
      Dual of Traversable.tailOption(), returning all elements except the last as Option.
      Specified by:
      initOption in interface Traversable<T>
      Returns:
      Some(traversable) or None if this is empty.
    • map

      <U> Seq<U> map(Function<? super T,? extends U> mapper)
      Description copied from interface: Traversable
      Maps the elements of this Traversable to elements of a new type preserving their order, if any.
      Specified by:
      map in interface Traversable<T>
      Specified by:
      map in interface Value<T>
      Type Parameters:
      U - Component type of the target Traversable
      Parameters:
      mapper - A mapper.
      Returns:
      a mapped Traversable
    • orElse

      Seq<T> orElse(Iterable<? extends T> other)
      Description copied from interface: Traversable
      Returns this Traversable if it is nonempty, otherwise return the alternative.
      Specified by:
      orElse in interface Traversable<T>
      Parameters:
      other - An alternative Traversable
      Returns:
      this Traversable if it is nonempty, otherwise return the alternative.
    • orElse

      Seq<T> orElse(Supplier<? extends Iterable<? extends T>> supplier)
      Description copied from interface: Traversable
      Returns this Traversable if it is nonempty, otherwise return the result of evaluating supplier.
      Specified by:
      orElse in interface Traversable<T>
      Parameters:
      supplier - An alternative Traversable supplier
      Returns:
      this Traversable if it is nonempty, otherwise return the result of evaluating supplier.
    • partition

      Tuple2<? extends Seq<T>,? extends Seq<T>> partition(Predicate<? super T> predicate)
      Description copied from interface: Traversable
      Creates a partition of this Traversable by splitting this elements in two in distinct traversables according to a predicate.
      Specified by:
      partition in interface Traversable<T>
      Parameters:
      predicate - A predicate which classifies an element if it is in the first or the second traversable.
      Returns:
      A disjoint union of two traversables. The first Traversable contains all elements that satisfy the given predicate, the second Traversable contains all elements that don't. The original order of elements is preserved.
    • peek

      Seq<T> peek(Consumer<? super T> action)
      Description copied from interface: Value
      Performs the given action on the first element if this is an eager implementation. Performs the given action on all elements (the first immediately, successive deferred), if this is a lazy implementation.
      Specified by:
      peek in interface Traversable<T>
      Specified by:
      peek in interface Value<T>
      Parameters:
      action - The action that will be performed on the element(s).
      Returns:
      this instance
    • replace

      Seq<T> replace(T currentElement, T newElement)
      Description copied from interface: Traversable
      Replaces the first occurrence (if exists) of the given currentElement with newElement.
      Specified by:
      replace in interface Traversable<T>
      Parameters:
      currentElement - An element to be substituted.
      newElement - A replacement for currentElement.
      Returns:
      a Traversable containing all elements of this where the first occurrence of currentElement is replaced with newElement.
    • replaceAll

      Seq<T> replaceAll(T currentElement, T newElement)
      Description copied from interface: Traversable
      Replaces all occurrences of the given currentElement with newElement.
      Specified by:
      replaceAll in interface Traversable<T>
      Parameters:
      currentElement - An element to be substituted.
      newElement - A replacement for currentElement.
      Returns:
      a Traversable containing all elements of this where all occurrences of currentElement are replaced with newElement.
    • retainAll

      Seq<T> retainAll(Iterable<? extends T> elements)
      Description copied from interface: Traversable
      Keeps all occurrences of the given elements from this.
      Specified by:
      retainAll in interface Traversable<T>
      Parameters:
      elements - Elements to be kept.
      Returns:
      a Traversable containing all occurrences of the given elements.
    • scan

      Seq<T> scan(T zero, BiFunction<? super T,? super T,? extends T> operation)
      Description copied from interface: Traversable
      Computes a prefix scan of the elements of the collection. Note: The neutral element z may be applied more than once.
      Specified by:
      scan in interface Traversable<T>
      Parameters:
      zero - neutral element for the operator op
      operation - the associative operator for the scan
      Returns:
      a new traversable collection containing the prefix scan of the elements in this traversable collection
    • scanLeft

      <U> Seq<U> scanLeft(U zero, BiFunction<? super U,? super T,? extends U> operation)
      Description copied from interface: Traversable
      Produces a collection containing cumulative results of applying the operator going left to right. Note: will not terminate for infinite-sized collections. Note: might return different results for different runs, unless the underlying collection type is ordered.
      Specified by:
      scanLeft in interface Traversable<T>
      Type Parameters:
      U - the type of the elements in the resulting collection
      Parameters:
      zero - the initial value
      operation - the binary operator applied to the intermediate result and the element
      Returns:
      collection with intermediate results
    • scanRight

      <U> Seq<U> scanRight(U zero, BiFunction<? super T,? super U,? extends U> operation)
      Description copied from interface: Traversable
      Produces a collection containing cumulative results of applying the operator going right to left. The head of the collection is the last cumulative result. Note: will not terminate for infinite-sized collections. Note: might return different results for different runs, unless the underlying collection type is ordered.
      Specified by:
      scanRight in interface Traversable<T>
      Type Parameters:
      U - the type of the elements in the resulting collection
      Parameters:
      zero - the initial value
      operation - the binary operator applied to the intermediate result and the element
      Returns:
      collection with intermediate results
    • slideBy

      Iterator<? extends Seq<T>> slideBy(Function<? super T,?> classifier)
      Description copied from interface: Traversable
      Slides a non-overlapping window of a variable size over this Traversable.

      Each window contains elements with the same class, as determined by classifier. Two consecutive values in this Traversable will be in the same window only if classifier returns equal values for them. Otherwise, the values will constitute the last element of the previous window and the first element of the next window.

      Examples:

      
       [].slideBy(Function.identity()) = []
       [1,2,3,4,4,5].slideBy(Function.identity()) = [[1],[2],[3],[4,4],[5]]
       [1,2,3,10,12,5,7,20,29].slideBy(x -> x/10) = [[1,2,3],[10,12],[5,7],[20,29]]
       
      Specified by:
      slideBy in interface Traversable<T>
      Parameters:
      classifier - A function which classifies elements into classes
      Returns:
      A new Iterator of windows of the grouped elements
    • sliding

      Iterator<? extends Seq<T>> sliding(int size)
      Description copied from interface: Traversable
      Slides a window of a specific size and step size 1 over this Traversable by calling Traversable.sliding(int, int).
      Specified by:
      sliding in interface Traversable<T>
      Parameters:
      size - a positive window size
      Returns:
      a new Iterator of windows of a specific size using step size 1
    • sliding

      Iterator<? extends Seq<T>> sliding(int size, int step)
      Description copied from interface: Traversable
      Slides a window of a specific size and step size over this Traversable.

      Examples:

       
       [].sliding(1,1) = []
       [1,2,3,4,5].sliding(2,3) = [[1,2],[4,5]]
       [1,2,3,4,5].sliding(2,4) = [[1,2],[5]]
       [1,2,3,4,5].sliding(2,5) = [[1,2]]
       [1,2,3,4].sliding(5,3) = [[1,2,3,4],[4]]
       
       
      Specified by:
      sliding in interface Traversable<T>
      Parameters:
      size - a positive window size
      step - a positive step size
      Returns:
      a new Iterator of windows of a specific size using a specific step size
    • span

      Tuple2<? extends Seq<T>,? extends Seq<T>> span(Predicate<? super T> predicate)
      Description copied from interface: Traversable
      Returns a tuple where the first element is the longest prefix of elements that satisfy the given predicate and the second element is the remainder.
      Specified by:
      span in interface Traversable<T>
      Parameters:
      predicate - A predicate.
      Returns:
      a Tuple containing the longest prefix of elements that satisfy p and the remainder.
    • tail

      Seq<T> tail()
      Description copied from interface: Traversable
      Drops the first element of a non-empty Traversable.
      Specified by:
      tail in interface Traversable<T>
      Returns:
      A new instance of Traversable containing all elements except the first.
    • tailOption

      Option<? extends Seq<T>> tailOption()
      Description copied from interface: Traversable
      Drops the first element of a non-empty Traversable and returns an Option.
      Specified by:
      tailOption in interface Traversable<T>
      Returns:
      Some(traversable) or None if this is empty.
    • take

      Seq<T> take(int n)
      Description copied from interface: Traversable
      Takes the first n elements of this or all elements, if this length < n.

      The result is equivalent to sublist(0, max(0, min(length(), n))) but does not throw if n < 0 or n > length().

      In the case of n < 0 the empty instance is returned, in the case of n > length() this is returned.

      Specified by:
      take in interface Traversable<T>
      Parameters:
      n - The number of elements to take.
      Returns:
      A new instance consisting of the first n elements of this or all elements, if this has less than n elements.
    • takeUntil

      Seq<T> takeUntil(Predicate<? super T> predicate)
      Description copied from interface: Traversable
      Takes elements until the predicate holds for the current element.

      Note: This is essentially the same as takeWhile(predicate.negate()). It is intended to be used with method references, which cannot be negated directly.

      Specified by:
      takeUntil in interface Traversable<T>
      Parameters:
      predicate - A condition tested subsequently for this elements.
      Returns:
      a new instance consisting of all elements before the first one which does satisfy the given predicate.
    • takeWhile

      Seq<T> takeWhile(Predicate<? super T> predicate)
      Description copied from interface: Traversable
      Takes elements while the predicate holds for the current element.
      Specified by:
      takeWhile in interface Traversable<T>
      Parameters:
      predicate - A condition tested subsequently for the contained elements.
      Returns:
      a new instance consisting of all elements before the first one which does not satisfy the given predicate.
    • takeRight

      Seq<T> takeRight(int n)
      Description copied from interface: Traversable
      Takes the last n elements of this or all elements, if this length < n.

      The result is equivalent to sublist(max(0, min(length(), length() - n)), n), i.e. takeRight will not throw if n < 0 or n > length().

      In the case of n < 0 the empty instance is returned, in the case of n > length() this is returned.

      Specified by:
      takeRight in interface Traversable<T>
      Parameters:
      n - The number of elements to take.
      Returns:
      A new instance consisting of the last n elements of this or all elements, if this has less than n elements.
    • takeRightUntil

      Seq<T> takeRightUntil(Predicate<? super T> predicate)
      Takes elements until the predicate holds for the current element, starting from the end.
      Parameters:
      predicate - A condition tested subsequently for this elements, starting from the end.
      Returns:
      a new instance consisting of all elements after the last one which does satisfy the given predicate.
      Throws:
      NullPointerException - if predicate is null
    • takeRightWhile

      Seq<T> takeRightWhile(Predicate<? super T> predicate)
      Takes elements while the predicate holds for the current element, starting from the end.

      Note: This is essentially the same as takeRightUntil(predicate.negate()). It is intended to be used with method references, which cannot be negated directly.

      Parameters:
      predicate - A condition tested subsequently for this elements, starting from the end.
      Returns:
      a new instance consisting of all elements after the last one which does not satisfy the given predicate.
      Throws:
      NullPointerException - if predicate is null
    • unzip

      <T1, T2> Tuple2<? extends Seq<T1>,? extends Seq<T2>> unzip(Function<? super T,Tuple2<? extends T1,? extends T2>> unzipper)
      Description copied from interface: Traversable
      Unzips this elements by mapping this elements to pairs which are subsequently split into two distinct sets.
      Specified by:
      unzip in interface Traversable<T>
      Type Parameters:
      T1 - 1st element type of a pair returned by unzipper
      T2 - 2nd element type of a pair returned by unzipper
      Parameters:
      unzipper - a function which converts elements of this to pairs
      Returns:
      A pair of set containing elements split by unzipper
    • unzip3

      <T1, T2, T3> Tuple3<? extends Seq<T1>,? extends Seq<T2>,? extends Seq<T3>> unzip3(Function<? super T,Tuple3<? extends T1,? extends T2,? extends T3>> unzipper)
      Description copied from interface: Traversable
      Unzips this elements by mapping this elements to triples which are subsequently split into three distinct sets.
      Specified by:
      unzip3 in interface Traversable<T>
      Type Parameters:
      T1 - 1st element type of a triplet returned by unzipper
      T2 - 2nd element type of a triplet returned by unzipper
      T3 - 3rd element type of a triplet returned by unzipper
      Parameters:
      unzipper - a function which converts elements of this to pairs
      Returns:
      A triplet of set containing elements split by unzipper
    • zip

      <U> Seq<Tuple2<T,U>> zip(Iterable<? extends U> that)
      Description copied from interface: Traversable
      Returns a traversable formed from this traversable and another Iterable collection by combining corresponding elements in pairs. If one of the two iterables is longer than the other, its remaining elements are ignored.

      The length of the returned traversable is the minimum of the lengths of this traversable and that iterable.

      Specified by:
      zip in interface Traversable<T>
      Type Parameters:
      U - The type of the second half of the returned pairs.
      Parameters:
      that - The Iterable providing the second half of each result pair.
      Returns:
      a new traversable containing pairs consisting of corresponding elements of this traversable and that iterable.
    • zipWith

      <U, R> Seq<R> zipWith(Iterable<? extends U> that, BiFunction<? super T,? super U,? extends R> mapper)
      Description copied from interface: Traversable
      Returns a traversable formed from this traversable and another Iterable collection by mapping elements. If one of the two iterables is longer than the other, its remaining elements are ignored.

      The length of the returned traversable is the minimum of the lengths of this traversable and that iterable.

      Specified by:
      zipWith in interface Traversable<T>
      Type Parameters:
      U - The type of the second parameter of the mapper.
      R - The type of the mapped elements.
      Parameters:
      that - The Iterable providing the second parameter of the mapper.
      mapper - a mapper.
      Returns:
      a new traversable containing mapped elements of this traversable and that iterable.
    • zipAll

      <U> Seq<Tuple2<T,U>> zipAll(Iterable<? extends U> that, T thisElem, U thatElem)
      Description copied from interface: Traversable
      Returns a traversable formed from this traversable and another Iterable by combining corresponding elements in pairs. If one of the two collections is shorter than the other, placeholder elements are used to extend the shorter collection to the length of the longer.

      The length of the returned traversable is the maximum of the lengths of this traversable and that iterable.

      Special case: if this traversable is shorter than that elements, and that elements contains duplicates, the resulting traversable may be shorter than the maximum of the lengths of this and that because a traversable contains an element at most once.

      If this Traversable is shorter than that, thisElem values are used to fill the result. If that is shorter than this Traversable, thatElem values are used to fill the result.

      Specified by:
      zipAll in interface Traversable<T>
      Type Parameters:
      U - The type of the second half of the returned pairs.
      Parameters:
      that - The Iterable providing the second half of each result pair.
      thisElem - The element to be used to fill up the result if this traversable is shorter than that.
      thatElem - The element to be used to fill up the result if that is shorter than this traversable.
      Returns:
      A new traversable containing pairs consisting of corresponding elements of this traversable and that.
    • zipWithIndex

      Seq<Tuple2<T,Integer>> zipWithIndex()
      Description copied from interface: Traversable
      Zips this traversable with its indices.
      Specified by:
      zipWithIndex in interface Traversable<T>
      Returns:
      A new traversable containing all elements of this traversable paired with their index, starting with 0.
    • zipWithIndex

      <U> Seq<U> zipWithIndex(BiFunction<? super T,? super Integer,? extends U> mapper)
      Description copied from interface: Traversable
      Zips this traversable with its indices by applying mapper provided.
      Specified by:
      zipWithIndex in interface Traversable<T>
      Type Parameters:
      U - The type of the mapped elements.
      Parameters:
      mapper - a mapper.
      Returns:
      a new traversable containing elements of this traversable, zipped with indices, and mapped with mapper provided.
    • withDefaultValue

      @Deprecated default Function1<Integer,T> withDefaultValue(T defaultValue)
      Deprecated.
      Will be removed
      Turns this sequence from a partial function into a total function that returns defaultValue for all indexes that are out of bounds.
      Parameters:
      defaultValue - default value to return for out of bound indexes
      Returns:
      a total function from index to T
    • withDefault

      @Deprecated default Function1<Integer,T> withDefault(Function<? super Integer,? extends T> defaultFunction)
      Deprecated.
      Will be removed
      Turns this sequence from a partial function into a total function that returns a value computed by defaultFunction for all indexes that are out of bounds.
      Parameters:
      defaultFunction - function to evaluate for all out of bounds indexes.
      Returns:
      a total function from index to T
    • isSequential

      default boolean isSequential()
      Description copied from interface: Traversable
      Checks if the elements of this Traversable appear in encounter order.
      Specified by:
      isSequential in interface Traversable<T>
      Returns:
      true, if the insertion order of elements is preserved, false otherwise.