peek_top-set: Assign to/modify the top of an rstack
In rstackdeque: Persistent Fast Amortized Stack and Queue Data Structures

Description Usage Arguments Details Value See Also Examples

Allows modification access to the top of a stack.

1	peek_top(s, ...) <- value

`s`	rstack to modify the first element of.
`...`	additional arguments to be passed to or from methods (ignored).
`value`	value to assign to the top data element.

Runs in O(1) worst case time. Throws an error if the rstack is empty. Modifies the element in place (i.e., is not side-effect-free).

modified rstack.

peek_top for accessing the top data element.

s <- rstack()
s <- insert_top(s, data.frame(a = 1, b = 1))
s <- insert_top(s, data.frame(a = 1, b = 1))

peek_top(s)$a <- 100
print(s)

peek_top(s) <- data.frame(a = 100, b = 100)