applyPairs -- apply a function to each pair in a hash table

Synopsis

• Usage:

  applyPairs(H, f)

• Inputs:
  • H, a hash table
  • f, a function, of two arguments, returning a pair or null
• Outputs:
  • a hash table, obtained by applying f to each key/value pair in H

Description

i1 : H = new HashTable from {1 => 10, 2 => 15, 3 => 20}

o1 = HashTable{1 => 10}
               2 => 15
               3 => 20

o1 : HashTable

i2 : applyPairs(H, (k,v) -> (k+1, v+10))

o2 = HashTable{2 => 20}
               3 => 25
               4 => 30

o2 : HashTable

i3 : applyPairs(H, (k,v) -> (v,k))

o3 = HashTable{10 => 1}
               15 => 2
               20 => 3

o3 : HashTable

Caveat

See also

• hash tables
• applyKeys -- apply a function to each key in a hash table
• applyValues -- apply a function to each value in a hash table
• pairs -- list the pairs in a hash table, dictionary, or basic list
• scanPairs -- apply a function to the pairs in a hash table