gololang

Class Tuple

java.lang.Object

gololang.Tuple

All Implemented Interfaces:

HeadTail<java.lang.Object>, java.lang.Comparable<Tuple>, java.lang.Iterable<java.lang.Object>

public final class Tuple
extends java.lang.Object
implements HeadTail<java.lang.Object>, java.lang.Comparable<Tuple>

Represents an tuple object.

A tuple essentially behaves like an immutable array. In Golo, tuples can be created as follows:

 # Short syntax
 let t1 = [1, 2, 3]

 # Complete collection literal syntax
 let t2 = tuple[1, 2, 3]
 

Constructor Summary

Constructors

Constructor and Description
Tuple(java.lang.Object... values) Creates a new tuple from values.

Method Summary

Modifier and Type	Method and Description
int	compareTo(Tuple other) Compares this tuple with the specified tuple for order.
Tuple	destruct() Helper for destructuring.
boolean	equals(java.lang.Object o)
static Tuple	fromArray(java.lang.Object[] values) Helper factory method.
java.lang.Object	get(int index) Gets the element at a specified index.
int	hashCode()
java.lang.Object	head() Returns the first element of the tuple.
boolean	isEmpty() Checks whether the tuple is empty or not.
java.util.Iterator<java.lang.Object>	iterator() Creates an iterator over the tuple.
int	size() Gives the number of elements in this tuple.
Tuple	subTuple(int start) Extract a sub-tuple.
Tuple	subTuple(int start, int end) Extract a sub-tuple.
Tuple	tail() Returns a new tuple containg the remaining elements.
java.lang.Object[]	toArray() Returns an array containing all of the elements in this tuple.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface gololang.HeadTail

toIterable

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

Tuple

public Tuple(java.lang.Object... values)

Creates a new tuple from values.

Parameters:

values - the tuple values.

Method Detail

fromArray

public static Tuple fromArray(java.lang.Object[] values)

Helper factory method.

Parameters:

values - the values as an array.

Returns:

a tuple from the array values.

size

public int size()

Gives the number of elements in this tuple.

Returns:

the tuple size.

isEmpty

public boolean isEmpty()

Checks whether the tuple is empty or not.

Specified by:

isEmpty in interface HeadTail<java.lang.Object>

Returns:

true if the tuple has no element, false otherwise.

get

public java.lang.Object get(int index)

Gets the element at a specified index.

Parameters:

index - the element index.

Returns:

the element at index index.

Throws:

java.lang.IndexOutOfBoundsException - if the specified index is not valid (negative value or above the size).

iterator

public java.util.Iterator<java.lang.Object> iterator()

Creates an iterator over the tuple.

The iterator does not support removal.

Specified by:

iterator in interface java.lang.Iterable<java.lang.Object>

Returns:

an iterator.

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class java.lang.Object

compareTo

public int compareTo(Tuple other)

Compares this tuple with the specified tuple for order.

Returns a negative integer, zero, or a positive integer as this tuple is less than, equal to, or greater than the specified tuple.

Two tuples are compared using the lexicographical (dictionary) order, that is: [1, 2] < [1, 3] and [2, 5] < [3, 1].

Two tuples are comparable if they have the same size and their elements are pairwise comparable.

Specified by:

compareTo in interface java.lang.Comparable<Tuple>

Parameters:

other - the tuple to be compared.

Returns:

a negative integer, zero, or a positive integer as this tuple is less than, equal to, or greater than the specified tuple.

Throws:

java.lang.NullPointerException - if the specified tuple is null.

java.lang.ClassCastException - if the type of the elements in the specified tuple prevent them from being compared to this tuple elements.

java.lang.IllegalArgumentException - if the specified tuple has a different size than this tuple.

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

head

public java.lang.Object head()

Returns the first element of the tuple.

Specified by:

head in interface HeadTail<java.lang.Object>

Returns:

the first element.

tail

public Tuple tail()

Returns a new tuple containg the remaining elements.

Specified by:

tail in interface HeadTail<java.lang.Object>

Returns:

a tuple.

destruct

public Tuple destruct()

Helper for destructuring.

Returns:

the tuple itself

subTuple

public Tuple subTuple(int start)

Extract a sub-tuple.

Parameters:

start - the index of the first element.

Returns:

a new tuple containing the elements from start to the end.

subTuple

public Tuple subTuple(int start,
                      int end)

Extract a sub-tuple.

Parameters:

start - the index of the first element (inclusive).

end - the index of the last element (exclusive).

Returns:

a new tuple containing the elements between indices start inclusive and end exclusive.

toArray

public java.lang.Object[] toArray()

Returns an array containing all of the elements in this tuple.

Returns:

an array of values