Add Elements to the Left of Deques

Add elements to left side of Deque objects.

addleft(.x, ...)

ref_addleft(.x, ...)

# S3 method for Deque
addleft(.x, ...)

# S3 method for Deque
ref_addleft(.x, ...)

Arguments

.x

a [Deque] object

...

elements to be added.

Value

For Deque, an object of class Deque with the elements being added to the left of .x.

Note

While addleft uses copy semantics ref_addleft work by reference.

Examples

d = deque(0)
add(d, a = 1, b = 2)         # |0, a = 1, b = 2|
#> |0, a = 1, b = 2|
addleft(d, a = 1, b = 2)     # |b = 2, a = 1, 0|
#> |b = 2, a = 1, 0|