bool :dict-contains ( array $ARR , mixed $ELEM , … )
bool :dict-contains ( dict $DICT , mixed $ELEM , … )
bool :arr-contains ( array $ARR , mixed $ELEM , … )
bool :arr-contains ( dict $DICT , mixed $ELEM , … )

Checks whether the given element is present in array/dictionary, using loose comparison (:eq).
Can be passed multiple values; will yield TRUE only if all elements are present.

It is recommended the array/dictionary is passed by reference, as this saves the work of copying the structure.

# :arr-contains example.
!fun :rand-arr $NUM
   :set &ARR :arr
   !while $NUM
      :set &ARR[:sub &NUM i1] :random i100
   !done
   :return &ARR
!nuf

:set &A :rand-arr i10
!if :arr-contains &A i50
    :writeln s'Yay, 50 is in the random array!'
    !else
    :writeln s'How sad, 50 was not rolled this time.'
    !fi