The Predicate <tt>where</tt>

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# The Predicate `where`

The predicate `where` is defined for each type. It simply copies its input parameter to its output parameter. Hence, it may be used to construct a value and assign it to a variable as in

       where(list(red, nil) -> L)

or to inspect a value and define variables with subterms as in

       where(L -> list(Head, Tail))

This predicate is of particular use in alternative statements and is discussed in the corresponding section.