| Type: | Package |
| Title: | Hash Table and Hash Set |
| Version: | 1.0.0 |
| Date: | 2026-7-17 |
| Depends: | R (≥ 4.0.0) |
| Imports: | methods, Rcpp, fastmatch |
| LinkingTo: | Rcpp |
| Suggests: | knitr, rmarkdown |
| Description: | It provides three implementations of hash tables and hash maps: 1. using 'std::unordered_map' and 'std::unordered_set' C++ libraries, 2. wrapping around the 'fastmatch' package, 3. using R environment. |
| URL: | https://github.com/jokergoo/hashtable, https://jokergoo.github.io/hashtable/ |
| VignetteBuilder: | knitr |
| BugReports: | https://github.com/jokergoo/hashtable/issues |
| License: | MIT + file LICENSE |
| Encoding: | UTF-8 |
| Config/roxygen2/version: | 8.0.0 |
| NeedsCompilation: | yes |
| Packaged: | 2026-07-17 16:59:57 UTC; guz |
| Author: | Zuguang Gu  [aut,
cre] |
| Maintainer: | Zuguang Gu <guzuguang@suat-sz.edu.cn> |
| Repository: | CRAN |
| Date/Publication: | 2026-07-27 14:40:08 UTC |
Generic functions
Description
Generic functions
Details
There are the following generic functions:
-
hash_exists(h, keys): tests whether keys exist. -
hash_keys(h): returns a vector of keys. -
hash_values(h, keys = NULL): returns a vector of values. -
hash_size(h): returns the size of the hash table or hash set. -
hash_insert(h, keys, ...): inserts new keys or modify values for existing keys. -
hash_delete(h, keys): deletes keys. -
hash_copy(h): makes a copy of the hash table or hash set.
They can be used on the hash object created by hash_table(), hash_set(), hash_fm_table(), hash_fm_set(), hash_env_table(), hash_env_set().
Value
hash_exists() returns a logical vector. hash_keys() returns a character vector.
hash_values() returns a single vector or a list.
hash_size() returns an integer scalar. hash_insert(), hash_delete()
and hash_copy() all return a hash table object.
Hash table and hash set implemented by environment
Description
Hash table and hash set implemented by environment
Usage
hash_env_table(keys, values)
hash_env_set(keys)
## S4 method for signature 'hash_env'
hash_exists(h, keys)
## S4 method for signature 'hash_env'
hash_delete(h, keys)
## S4 method for signature 'hash_env_table'
hash_insert(h, keys, values)
## S4 method for signature 'hash_env_set'
hash_insert(h, keys)
## S4 method for signature 'hash_env'
hash_size(h)
## S3 method for class 'hash_env'
length(x)
## S4 method for signature 'hash_env'
hash_keys(h)
## S4 method for signature 'hash_env_table'
hash_values(h, keys = NULL)
## S4 method for signature 'hash_env_set'
hash_values(h, keys = NULL)
## S4 method for signature 'hash_env'
hash_copy(h)
## S3 method for class 'hash_env_table'
x[[i]]
## S3 method for class 'hash_env_set'
x[[i]]
## S3 replacement method for class 'hash_env_table'
x[[i]] <- value
## S3 method for class 'hash_env_table'
x[i]
## S3 method for class 'hash_env_set'
x[i]
## S3 replacement method for class 'hash_env_table'
x[i] <- value
## S3 method for class 'hash_env'
x$name
## S3 replacement method for class 'hash_env_table'
x$i <- value
## S3 replacement method for class 'hash_env_set'
x[[i]] <- value
## S3 replacement method for class 'hash_env_set'
x[i] <- value
## S3 replacement method for class 'hash_env_set'
x$name <- value
as.hash_env(x)
## Default S3 method:
as.hash_env(x)
## S3 method for class 'hash_env_set'
as.vector(x, mode = "any")
## S3 method for class 'hash_env_table'
as.vector(x, mode = "any")
## S3 method for class 'hash_env_table'
as.list(x, ...)
## S4 method for signature 'hash_env_table'
show(object)
## S4 method for signature 'hash_env_set'
show(object)
Arguments
keys |
A character vector. Keys should have no duplicates. |
values |
An atomic vector or a list. |
h, x, object |
A |
i, name, value |
Keys and values. |
mode, ... |
Please ignore. |
Details
hash_values() and [ methods on the hash_env_table object preserve the original format of values, which means, if values
was specified as an atomic vector, the two functions also returns atomic vectors.
Value
hash_env_table() returns a hash_env_table object. hash_env_set() returns a hash_env_set object.
hash_env_delete(), hash_env_insert(), hash_env_copy() return a hash_env_table object
or a hash_env_set object. hash_exists() returns a logical vector. hash_size() returns an integer. hash_keys() returns
a character vector. hash_values() on the hash_env_table object returns a vector of a list which has the same format as in the
constructor function. hash_values() on the hash_env_set object throws an error.
Examples
h = hash_env_table(letters, 1:26)
hash_keys(h)
hash_values(h)
h$a
h = hash_env_set(letters)
hash_exists(h, "a")
Hash table and hash set implemented by fastmatch
Description
Hash table and hash set implemented by fastmatch
Usage
hash_fm_table(keys, values)
hash_fm_set(keys)
## S4 method for signature 'hash_fm'
hash_exists(h, keys)
## S4 method for signature 'hash_fm'
hash_delete(h, keys)
## S4 method for signature 'hash_fm'
hash_size(h)
## S3 method for class 'hash_fm'
length(x)
## S4 method for signature 'hash_fm'
hash_keys(h)
## S4 method for signature 'hash_fm_table'
hash_values(h, keys = NULL)
## S4 method for signature 'hash_fm_set'
hash_values(h, keys = NULL)
## S4 method for signature 'hash_fm_table'
hash_insert(h, keys, values)
## S4 method for signature 'hash_fm_set'
hash_insert(h, keys, values)
## S4 method for signature 'hash_fm'
hash_copy(h)
## S3 method for class 'hash_fm_table'
x[[i]]
## S3 method for class 'hash_fm_set'
x[[i]]
## S3 replacement method for class 'hash_fm_table'
x[[i]] <- value
## S3 method for class 'hash_fm_table'
x[i]
## S3 method for class 'hash_fm_set'
x[i]
## S3 replacement method for class 'hash_fm_table'
x[i] <- value
## S3 method for class 'hash_fm'
x$name
## S3 replacement method for class 'hash_fm_table'
x$i <- value
## S3 replacement method for class 'hash_fm_set'
x[[i]] <- value
## S3 replacement method for class 'hash_fm_set'
x[i] <- value
## S3 replacement method for class 'hash_fm_set'
x$name <- value
as.hash_fm(x)
## Default S3 method:
as.hash_fm(x)
## S3 method for class 'hash_fm_set'
as.vector(x, mode = "any")
## S3 method for class 'hash_fm_table'
as.vector(x, mode = "any")
## S3 method for class 'hash_fm_table'
as.list(x, ...)
## S4 method for signature 'hash_fm_table'
show(object)
## S4 method for signature 'hash_fm_set'
show(object)
Arguments
keys |
A character vector. Keys should have no duplicates. |
values |
An atomic vector or a list. |
h, x, object |
A |
i, name, value |
Keys and values. |
mode, ... |
Please ignore. |
Details
hash_values() and [ methods on the hash_fm_table object preserve the original format of values, which means, if values
was specified as an atomic vector, the two functions also returns atomic vectors.
Once the hash table or the hash set is created, it is not allowed to modify.
Value
hash_fm_table() returns a hash_fm_table object. hash_fm_set() returns a hash_fm_set object.
hash_fm_delete(), hash_fm_insert(), hash_fm_copy() return a hash_fm_table object
or a hash_fm_set object. hash_exists() returns a logical vector. hash_size() returns an integer. hash_keys() returns
a character vector. hash_values() on the hash_fm_table object returns a vector of a list which has the same format as in the
constructor function. hash_values() on the hash_fm_set object throws an error.
Examples
h = hash_fm_table(letters, 1:26)
hash_keys(h)
hash_values(h)
h$a
try(h$a <- 2L)
h = hash_fm_set(letters)
hash_exists(h, "a")
Hash set implemented by std::unordered_set
Description
Hash set implemented by std::unordered_set
Usage
hash_set(keys)
## S4 method for signature 'hash_unordered_set'
hash_exists(h, keys)
## S4 method for signature 'hash_unordered_set'
hash_insert(h, keys)
## S4 method for signature 'hash_unordered_set'
hash_delete(h, keys)
## S4 method for signature 'hash_unordered_set'
hash_size(h)
## S4 method for signature 'hash_unordered_set'
hash_copy(h)
## S4 method for signature 'hash_unordered_set'
hash_keys(h)
## S4 method for signature 'hash_unordered_set'
hash_values(h, keys = NULL)
## S3 method for class 'hash_unordered_set'
x[[i]]
## S3 method for class 'hash_unordered_set'
x[i]
## S3 method for class 'hash_unordered_set'
x$name
## S3 replacement method for class 'hash_unordered_set'
x[[i]] <- value
## S3 replacement method for class 'hash_unordered_set'
x[i] <- value
## S3 replacement method for class 'hash_unordered_set'
x$name <- value
## S3 method for class 'hash_unordered_set'
length(x)
## S4 method for signature 'hash_unordered_set'
show(object)
as.hash_set(x)
## Default S3 method:
as.hash_set(x)
## S3 method for class 'hash_unordered_set'
as.vector(x, mode = "any")
Arguments
keys |
A character vector. Keys should have no duplicates. |
h, x, object |
A |
i, name, value |
Keys and values. |
mode |
Please ignore. |
Details
Hash set has no values associated.
$, [[ and [ return logical vectors. $<-, [[<- and [<- insert or delete keys.
Value
hash_set(), hash_insert(), hash_delete(), hash_copy() returns a hash_unordered_set object.
hash_exists() returns a logical vector. hash_size() returns an integer. hash_keys() returns
a character vector. hash_values() throws an error.
Examples
h = hash_set(letters)
hash_exists(h, c("a", "b", "foo"))
hash_insert(h, "foo")
hash_delete(h, "foo")
h$a
h$foo
as.hash_set(letters)
Hash table implemented by std::unordered_map
Description
Hash table implemented by std::unordered_map
Usage
hash_table(keys, values)
## S4 method for signature 'hash_unordered_map'
hash_values(h, keys = NULL)
## S4 method for signature 'hash_unordered_map'
hash_exists(h, keys)
## S4 method for signature 'hash_unordered_map'
hash_insert(h, keys, values)
## S4 method for signature 'hash_unordered_map'
hash_delete(h, keys)
## S4 method for signature 'hash_unordered_map'
hash_size(h)
## S3 method for class 'hash_unordered_map'
length(x)
## S4 method for signature 'hash_unordered_map'
hash_keys(h)
## S4 method for signature 'hash_unordered_map'
hash_copy(h)
## S3 method for class 'hash_unordered_map'
x[[i]]
## S3 method for class 'hash_unordered_map'
x[i]
## S3 method for class 'hash_unordered_map'
x$name
## S3 replacement method for class 'hash_unordered_map'
x[[i]] <- value
## S3 replacement method for class 'hash_unordered_map'
x[i] <- value
## S3 replacement method for class 'hash_unordered_map'
x$name <- value
## S4 method for signature 'hash_unordered_map'
show(object)
as.hash_table(x)
## Default S3 method:
as.hash_table(x)
## S3 method for class 'hash_unordered_map'
as.vector(x, mode = "any")
## S3 method for class 'hash_unordered_map'
as.list(x, ...)
Arguments
keys |
A character vector. Keys should have no duplicates. |
values |
An atomic vector or a list. |
h, x, object |
A |
i, name, value |
Keys and values. |
mode, ... |
Please ignore. |
Details
hash_values() and [ methods preserve the original format of values, which means, if values
was specified as an atomic vector, the two functions also returns atomic vectors.
Value
hash_table(), hash_insert(), hash_delete(), hash_copy() returns a hash_unordered_map object.
hash_exists() returns a logical vector. hash_size() returns an integer. hash_keys() returns
a character vector. hash_values() returns a vector of a list which has the same format as in the
constructor function.
Examples
hash_table(c("a", "b"), 1:2L)
hash_table(c("a", "b"), c(TRUE, FALSE))
hash_table(c("a", "b"), c(0.1, 0.2))
hash_table(c("a", "b"), c("one", "two"))
hash_table(c("a", "b"), as.Date(c("2025-01-01", "2025-02-01")))
hash_table(c("a", "b"), as.POSIXct(c("2025-01-01 00:00:01", "2025-02-01 00:00:01")))
hash_table(c("a", "b"), list(1:10, letters))
h = hash_table(letters, 1:26)
hash_keys(h)
hash_values(h)
hash_exists(h, c("a", "b", "foo"))
hash_delete(h, letters[1:20]); h
hash_insert(h, "foo", 100L)
h = hash_table(letters, 1:26)
h$a
h[["a"]]
h[c("a", "b")]
as.vector(h)
as.list(h)