| Type: | Package |
| Title: | High Performance Container Data Types |
| Version: | 0.3.9 |
| Date: | 2025-08-16 |
| Description: | Provides high performance container data types such as queues, stacks, deques, dicts and ordered dicts. Benchmarks https://randy3k.github.io/collections/articles/benchmark.html have shown that these containers are asymptotically more efficient than those offered by other packages. |
| License: | MIT + file LICENSE |
| URL: | https://github.com/randy3k/collections/ |
| Suggests: | testthat (≥ 2.3.1) |
| ByteCompile: | yes |
| Encoding: | UTF-8 |
| NeedsCompilation: | yes |
| RoxygenNote: | 7.1.0 |
| Packaged: | 2025-08-18 17:06:46 UTC; randylai |
| Author: | Randy Lai [aut, cre], Andrea Mazzoleni [cph] (tommy hash table library), Yann Collet [cph] (xxhash algorithm) |
| Maintainer: | Randy Lai <randy.cs.lai@gmail.com> |
| Repository: | CRAN |
| Date/Publication: | 2025-08-18 18:10:15 UTC |
collections: High Performance Container Data Types
Description
Provides high performance container data types such as queues, stacks, deques, dicts and ordered dicts. Benchmarks <https://randy3k.github.io/collections/articles/benchmark.html> have shown that these containers are asymptotically more efficient than those offered by other packages.
Author(s)
Maintainer: Randy Lai randy.cs.lai@gmail.com
Other contributors:
Andrea Mazzoleni (tommy hash table library) [copyright holder]
Yann Collet (xxhash algorithm) [copyright holder]
See Also
Useful links:
Inspect objects
Description
cls is a replacement for the class function
which also works for the collection objects. It falls back to the ordinary class function
for other objects.
Usage
cls(x)
Arguments
x |
a collection object |
Examples
d <- dict()
cls(d)
Deprecated Functions
Description
Deprecated Functions
Usage
Deque(...)
Dict(...)
OrderedDict(...)
PriorityQueue(...)
Queue(...)
Stack(...)
Arguments
... |
anything |
Double Ended Queue
Description
deque creates a double ended queue.
Usage
deque(items = NULL)
Arguments
items |
a list of items |
Details
Following methods are exposed:
.$push(item) .$pushleft(item) .$pop() .$popleft() .$peek() .$peekleft() .$extend(q) .$extendleft(q) .$remove(item) .$clear() .$size() .$as_list() .$print()
-
item: any R object -
q: a deque object
See Also
Examples
q <- deque()
q$push("foo")
q$push("bar")
q$pushleft("baz")
q$pop() # bar
q$popleft() # baz
q <- deque(list("foo", "bar"))
q$push("baz")$pushleft("bla")
Dictionary
Description
dict creates an ordinary (unordered) dictionary (a.k.a. hash).
Usage
dict(items = NULL, keys = NULL)
Arguments
items |
a list of items |
keys |
a list of keys, use |
Details
Following methods are exposed:
.$set(key, value) .$get(key, default) .$remove(key, silent = FALSE) .$pop(key, default) .$has(key) .$keys() .$values() .$update(d) .$clear() .$size() .$as_list() .$print()
-
key: a scalar character, an atomic vector, an enviroment or a function -
value: any R object, value of the item -
default: optional, the default value of an item if the key is not found -
d: a dict object
See Also
Examples
d <- dict(list(apple = 5, orange = 10))
d$set("banana", 3)
d$get("apple")
d$as_list() # unordered
d$pop("orange")
d$as_list() # "orange" is removed
d$set("orange", 3)$set("pear", 7) # chain methods
# vector indexing
d$set(c(1L, 2L), 3)$set(LETTERS, 26)
d$get(c(1L, 2L)) # 3
d$get(LETTERS) # 26
# object indexing
e <- new.env()
d$set(sum, 1)$set(e, 2)
d$get(sum) # 1
d$get(e) # 2
Ordered Dictionary
Description
ordered_dict creates an ordered dictionary.
Usage
ordered_dict(items = NULL, keys = NULL)
Arguments
items |
a list of items |
keys |
a list of keys, use |
Details
Following methods are exposed:
.$set(key, value) .$get(key, default) .$remove(key, silent = FALSE) .$pop(key, default) .$popitem(last = TRUE) .$has(key) .$keys() .$values() .$update(d) .$clear() .$size() .$as_list() .$print()
-
key: scalar character, environment or function -
value: any R object, value of the item -
default: optional, the default value of an item if the key is not found -
d: an ordered_dict object
See Also
Examples
d <- ordered_dict(list(apple = 5, orange = 10))
d$set("banana", 3)
d$get("apple")
d$as_list() # the order the item is preserved
d$pop("orange")
d$as_list() # "orange" is removed
d$set("orange", 3)$set("pear", 7) # chain methods
Priority Queue
Description
priority_queue creates a priority queue (a.k.a heap).
Usage
priority_queue(items = NULL, priorities = rep(0, length(items)))
Arguments
items |
a list of items |
priorities |
a vector of interger valued priorities |
Details
Following methods are exposed:
.$push(item, priority = 0) .$pop() .$clear() .$size() .$as_list() .$print()
-
item: any R object -
priority: a real number, item with larger priority pops first
Examples
q <- priority_queue()
q$push("not_urgent")
q$push("urgent", priority = 2)
q$push("not_as_urgent", priority = 1)
q$pop() # urgent
q$pop() # not_as_urgent
q$pop() # not_urgent
q <- priority_queue(list("not_urgent", "urgent"), c(0, 2))
q$push("not_as_urgent", 1)$push("not_urgent2")
Queue
Description
queue creates a queue.
Usage
queue(items = NULL)
Arguments
items |
a list of items |
Details
Following methods are exposed:
.$push(item) .$pop() .$peek() .$clear() .$size() .$as_list() .$print()
-
item: any R object
See Also
Examples
q <- queue()
q$push("first")
q$push("second")
q$pop() # first
q$pop() # second
q <- queue(list("foo", "bar"))
q$push("baz")$push("bla")
Stack
Description
stack creates a stack.
Usage
stack(items = NULL)
Arguments
items |
a list of items |
Details
Following methods are exposed:
.$push(item) .$pop() .$peek() .$clear() .$size() .$as_list() .$print()
-
item: any R object
See Also
Examples
s <- stack()
s$push("first")
s$push("second")
s$pop() # second
s$pop() # first
s <- stack(list("foo", "bar"))
s$push("baz")$push("bla")