| Title: | Don't Get Stuck with Stacks in R |
|---|---|
| Description: | Functions to create and manipulate FIFO (First In First Out), LIFO (Last In First Out), and NINO (Not In or Never Out) stacks in R. |
| Authors: | Paul Poncet [aut, cre] |
| Maintainer: | Paul Poncet <[email protected]> |
| License: | MIT + file LICENSE |
| Version: | 0.1.5 |
| Built: | 2024-10-27 05:50:03 UTC |
| Source: | https://github.com/paulponcet/flifo |
flifo provides functions to create and manipulate FIFO (First In First Out), LIFO (Last In First Out), and NINO (Not In or Never Out) stacks in R, most notably:
This method tests if a stack x is empty.
## S3 method for class 'stack' is.empty(x)## S3 method for class 'stack' is.empty(x)
x |
A stack. |
A logical, TRUE if x is empty.
The generic function is.empty
in package bazar.
The fifo, lifo, and nino functions
create 'First In First Out', 'Last In First Out', and
'Not In or Never Out' stacks, respectively.
is.stack(x) is.fifo(x) is.lifo(x) is.nino(x) ## S3 method for class 'stack' as.list(x, ...) fifo(max_length = Inf, max_size = Inf) lifo(max_length = Inf, max_size = Inf) nino(max_length = Inf, max_size = Inf)is.stack(x) is.fifo(x) is.lifo(x) is.nino(x) ## S3 method for class 'stack' as.list(x, ...) fifo(max_length = Inf, max_size = Inf) lifo(max_length = Inf, max_size = Inf) nino(max_length = Inf, max_size = Inf)
x |
An object to be tested or coerced. |
... |
Additional arguments. |
max_length |
numeric. The maximum (infinite by default) number of objects the stack can contain. |
max_size |
numeric. The maximum (infinite by default) size of the stack, in octets. |
is.xxx functions return a logical.
fifo, lifo, and nino return
an empty FIFO, LIFO, or NINO stack.
The function max_length returns the maximum number
of objects a stack can contains; this number can be changed
with max_length<-.
max_length(.stack) max_length(x) <- valuemax_length(.stack) max_length(x) <- value
.stack, x
|
A stack. |
value |
numeric. The new maximum length of the stack. |
max_length returns a (possibly infinite)
nonnegative numeric.
The pop function retrieves the first reachable
object from .stack.
pop(.stack)pop(.stack)
.stack |
A stack. |
The pop function is not pure. Side effect is that
.stack is modified in the calling environment.
The object retrieved.
If .stack is empty, an error is thrown.
push.
(s <- lifo(max_length = 3)) # empty LIFO (push(s, 0.3)) # (push(s, data.frame(x=1:2, y=2:3))) obj <- pop(s) # get the last element inserted(s <- lifo(max_length = 3)) # empty LIFO (push(s, 0.3)) # (push(s, data.frame(x=1:2, y=2:3))) obj <- pop(s) # get the last element inserted
The function print.stack
prints the class of the stack x (FIFO, LIFO, or NINO) and displays
its next reachable object.
## S3 method for class 'stack' print(x, ...)## S3 method for class 'stack' print(x, ...)
x |
A stack. |
... |
Additional arguments. |
The stack x is returned invisibly.
The push function inserts an
object into .stack.
push(.stack, x)push(.stack, x)
.stack |
A stack. |
x |
An object to insert in |
The push function is not pure. Side effects (made on purpose) are:
.stack is modified in the calling environment;
x is removed (deleted) if it exists in the calling environment.
NULL is returned invisibly.
pop.
(s <- lifo(max_length = 3)) # empty LIFO (push(s, 0.3)) # (push(s, data.frame(x=1:2, y=2:3))) obj <- pop(s) # get the last element inserted(s <- lifo(max_length = 3)) # empty LIFO (push(s, 0.3)) # (push(s, data.frame(x=1:2, y=2:3))) obj <- pop(s) # get the last element inserted
The function size returns the size of a stack, in bytes.
The function max_size returns the maximum number
of objects a stack can contains; this number can be changed
with max_size<-.
size(.stack) max_size(.stack) max_size(x) <- valuesize(.stack) max_size(.stack) max_size(x) <- value
.stack |
A stack. |
x |
A stack. |
value |
numeric. The new maximum size of the stack. |
size always returns a nonnegative numeric.
max_size returns a (possibly infinite) nonnegative numeric.