subsetting_hashtables: Subsetting 'hashset's and 'hashmap's
In r2r: R-Object to R-Object Hash Maps

subsetting_hashtables

R Documentation

Subsetting `hashset`s and `hashmap`s

Description

Subsetting operators `[[` and `[` for hashsets and hashmaps provide an equivalent synthax for the basic read/write operations performed by insert(), delete() and query().

Usage

## S3 method for class 'r2r_hashmap'
x[[i]]

## S3 method for class 'r2r_hashmap'
x[i]

## S3 replacement method for class 'r2r_hashmap'
x[[i]] <- value

## S3 replacement method for class 'r2r_hashmap'
x[i] <- value

## S3 method for class 'r2r_hashset'
x[[i]]

## S3 method for class 'r2r_hashset'
x[i]

## S3 replacement method for class 'r2r_hashset'
x[[i]] <- value

## S3 replacement method for class 'r2r_hashset'
x[i] <- value

Arguments

`x`	an `hashset` or `hashmap`.
`i`	for `[[`-subsetting, an arbitrary R object, the key to be queried or inserted/deleted from the hash tables. For `[`-subsetting, a list or an atomic vector whose individual elements correspond to the keys.
`value`	for `[[`-subsetting: `TRUE` or `FALSE` if `x` is an `hashset`, an arbitrary R object if `x` is an `hashmap`. In the case of `hashset`s, setting a key's value to `TRUE` and `FALSE` is equivalent to inserting and deleting, respectively, such key from the set. For `[`-subsetting, `value` must be a list or an atomic vector of the same length of `i`, whose individual elements are the values associated to the corresponding keys in the hash table.

Value

the replacement forms (⁠[[<-⁠ and ⁠[<-⁠) always return value. `[[` returns TRUE or FALSE if x is an hashset, an arbitrary R object if x is an hashmap and i is a valid key; when i is not a key, the behaviour for hashmaps depends on the value of on_missing_key(x). The `[` operator returns a list of the same length of i, whose k-th element is given by x[[ i[[k]] ]] (the remark on missing keys for hashmaps applies also here).