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--- status: DRAFT
--- author(s): L.Gold, Lily Silverstein
--- notes:
doc ///
Key
applyPairs
(applyPairs,HashTable,Function)
(applyPairs,BasicList,Function)
(applyPairs,Dictionary,Function)
(applyPairs,Thing,Function)
Headline
apply a function to each pair in a hash table
Usage
applyPairs(H, f)
Inputs
H:{HashTable, BasicList, Dictionary}
or any instance of a class with an @TO iterator@ method installed
f:Function
of two arguments, returning a pair or @TO null@
Outputs
:HashTable
obtained by applying {\tt f} to each key/value pair in {\tt H}
Description
Example
H = new HashTable from {1 => 10, 2 => 15, 3 => 20}
applyPairs(H, (k,v) -> (k+1, v+10))
applyPairs(H, (k,v) -> (v,k))
Text
If @CODE "H"@ is not a hash table, then @M2CODE "apply(pairs H, f)"@ is
called.
Example
applyPairs({4, 5, 6}, (i, x) -> i * x)
Caveat
It is an error for the function {\tt f} to return two pairs with the same key.
SeeAlso
"hash tables"
applyKeys
applyValues
pairs
scanPairs
///
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