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hash (version 2.1.0.1)

hash: hash/associative array/dictionary data structure for the R language

Description

Preferred constructor for the hash-class.

Usage

hash(...)

is.hash(x)

as.list.hash(x, all.names = FALSE, ... )

Arguments

Value

For hash, an object of class hash.

Details

hash returns a hash object. Key-value pairs may be specified via the ... argument as explicity arguments keys and values, as named key-value pairs, as a named vector or as implicit key, value vectors. See examples below for each type. Keys must be a valid R name, must be a character vector and must not be the empty string, "". Values are restricted to any valid R objects.

See .set for further details and how key-value vectors of unequal length are interpretted.

Hashes may be accessed via the standard R accessors [, [[ and $. See hash-accessors for details. is.hash returns a boolean value indicating if the argument is a hash object.

as.list.hash coerces the hash to a list.

See Also

.set, hash-accessors

Examples

Run this code
hash()

  hash( key=letters, values=1:26 )
  
  hash( 1:3, lapply(1:3, seq, 1 ))
  
  hash( a=1, b=2, c=3 )
  hash( c(a=1, b=2, c=3) ) 
  hash( list(a=1,b=2,c=3) )

  hash( c("foo","bar","baz"), 1:3 )
  hash( c("foo","bar","baz"),  lapply(1:3, seq, 1 ) )
  hash( letters, 1:26 )

  h <- hash( letters, 1:26 )
  h$a
  h$b
  h[[ "a" ]]
  h[ letters[1:3] ]

  h$a<-100
  # h[['a']]<-letters

  is.hash(h)
  as.list(h)

  clear(h)
  rm(h)

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