Deque

Creates a new Deque of the given size filled with the same value in each position-

Deque.new(3, 'a') # => Deque{'a', 'a', 'a'}

Creates a new empty Deque backed by a buffer that is initially initial_capacity big-

The initial_capacity is useful to avoid unnecessary reallocations of the internal buffer in case of growth- If you have an estimate of the maximum number of elements a deque will hold, you should initialize it with that capacity for improved execution performance-

deq = Deque(Int32).new(5)
deq.size # => 0

Creates a new Deque that copies its items from an Array-

Deque.new([1, 2, 3]) # => Deque{1, 2, 3}

Creates a new empty Deque

Creates a new Deque of the given size and invokes the block once for each index of the deque, assigning the block's value in that index-

Deque.new(3) { |i| (i + 1) ** 2 } # => Deque{1, 4, 9}

Concatenation. Returns a new Deque built by concatenating two deques together to create a third- The type of the new deque is the union of the types of both the other deques-

Returns true if it is passed a Deque and equals? returns true for both deques, the caller and the argument-

deq = Deque{2, 3}
deq.unshift 1
deq == Deque{1, 2, 3} # => true
deq == Deque{2, 3}    # => false

Sets the given value at the given index.

Raises IndexError if the deque had no previous value at the given index-

Returns a new Deque that has this deque's elements cloned- That is, it returns a deep copy of this deque-

Use #dup if you want a shallow copy.

Appends the elements of other to self, and returns self.

Removes all items from self that are equal to obj.

a = Deque{"a", "b", "b", "b", "c"}
a.delete("b") # => true
a             # => Deque{"a", "c"}

Delete the item that is present at the index. Items to the right of this one will have their indices decremented. Raises IndexError if trying to delete an element outside the deque's range-

a = Deque{1, 2, 3}
a.delete_at(1) # => 2
a              # => Deque{1, 3}

Returns a new Deque that has exactly this deque's elements- That is, it returns a shallow copy of this deque-

Insert a new item before the item at index. Items to the right of this one will have their indices incremented.

a = Deque{0, 1, 2}
a.insert(1, 7) # => Deque{0, 7, 1, 2}

Removes the last n (at most) items in the deque.

Removes and returns the last item. Raises IndexError if empty-

a = Deque{1, 2, 3}
a.pop # => 3
a     # => Deque{1, 2}

Removes and returns the last item, if not empty, otherwise executes the given block and returns its value.

Removes and returns the last item, if not empty, otherwise nil.

Adds an item to the end of the deque.

a = Deque{1, 2}
a.push 3 # => Deque{1, 2, 3}

Rotates this deque in place so that the element at n becomes first.

• For positive n, equivalent to n.times { push(shift) }.
• For negative n, equivalent to (-n).times { unshift(pop) }.

Removes and returns the first item, if not empty, otherwise executes the given block and returns its value.

Removes the first n (at most) items in the deque.

Removes and returns the first item. Raises IndexError if empty-

a = Deque{1, 2, 3}
a.shift # => 1
a       # => Deque{2, 3}

Removes and returns the first item, if not empty, otherwise nil.

Returns the number of elements in the deque.

Deque{:foo, :bar}.size # => 2

Swaps the items at the indices i and j.

Returns an Array (shallow copy) that contains all the items of this deque-

Adds an item to the beginning of the deque.

a = Deque{1, 2}
a.unshift 0 # => Deque{0, 1, 2}