Documentation for routine grabpairs
Documentation for routine grabpairs, assembled from the following types:
multi method grabpairs(Baggy: --> Any)multi method grabpairs(Baggy: --> Seq)
Pair or a
Pairs depending on the version of the method being invoked. Each
Pair returned has an element of the invocant as its key and the elements weight as its value. Unlike pickpairs, it works only on mutable structures, e.g. BagHash. Use of
grabpairs on 'an immutable structure results in an
X::Immutable exception. If
* is passed as
$count is greater than or equal to the number of elements of the invocant, then all element/weight
Pairs from the invocant are returned in a random sequence.
grabpairs different from pickpairs is that the 'grabbed' elements are in fact removed from the invocant.
my = (eggs => 2, bacon => 3).BagHash;say .grabpairs; # OUTPUT: «bacon => 3␤»say ; # OUTPUT: «BagHash.new(eggs(2))␤»say .grabpairs(1); # OUTPUT: «(eggs => 2)␤»say .grabpairs(*); # OUTPUT: «()␤»my = ('eggs' => 2, 'bacon' => 3).Bag;say .grabpairs;CATCH ;# OUTPUT: «X::Immutable: Cannot call 'grabpairs' on an immutable 'Bag'␤»
method grabpairs( = 1)
$count elements chosen at random (without repetition) from the set, and returns a list of
Pair objects whose keys are the grabbed elements and whose values are
* is passed as
$count is greater than or equal to the size of the set, then all its elements are removed and returned as
Pairs in the aforementioned way in random order.
Only works on mutable sets; When used on an immutable set, it results in an exception.