Description
Ordered Containers with Integer Keys.
Description
Provides a key-value store data structure. The keys are integers and the values can be any R object. This is like a list but indexed by a set of integers, not necessarily contiguous and possibly negative. The implementation uses a 'R6' class. These containers are not faster than lists but their usage can be more convenient for certain situations.
README.md
intmap
Ordered containers with integer keys.
- Create a new integer map.
imap <- intmap$new(
keys = c(11, -2), values = list(c("a", "b"), list(333, 4444, 55555))
)
imap
## `intmap` object containing 2 items:
##
## "-2" -> list: 333, 4444, 55555
## "11" -> character vector: a, b
- How many entries are there in the map?
imap$size()
## [1] 2
- Get the keys (always ordered) and the values.
imap$keys()
## [1] -2 11
imap$values()
## [[1]]
## [[1]][[1]]
## [1] 333
##
## [[1]][[2]]
## [1] 4444
##
## [[1]][[3]]
## [1] 55555
##
##
## [[2]]
## [1] "a" "b"
- Get the item of a given key.
imap$at(5)
## Nothing
imap$at(11)
## Just
## [1] "a" "b"
from_just(imap$at(11))
## [1] "a" "b"
- Or use the
getmethod with a default value.
imap$get(5, default = "I am missing.")
## [1] "I am missing."
imap$get(-2)
## [[1]]
## [1] 333
##
## [[2]]
## [1] 4444
##
## [[3]]
## [1] 55555
- Insert a new entry.
imap$insert(5, "I am not missing.")
## [1] TRUE
imap
## `intmap` object containing 3 items:
##
## "-2" -> list: 333, 4444, 55555
## "5" -> character: I am not missing.
## "11" -> character vector: a, b
- Get a submap.
imap$extract(c(5, 11, 99999))
## `intmap` object containing 2 items:
##
## "5" -> character: I am not missing.
## "11" -> character vector: a, b
- Merge with another map.
imap2 <- intmap$new(
c(-2, 0, 1),
list("I will be ignored", iris, mtcars)
)
imap$merge(imap2)
imap
## `intmap` object containing 5 items:
##
## "-2" -> list: 333, 4444, 55555
## "0" -> data.frame
## "1" -> data.frame
## "5" -> character: I am not missing.
## "11" -> character vector: a, b