Not (SelectionCriterion function)

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Matches an item if it does not meet the criterion (SelectionCriterion class)

This shared method creates a new SelectionCriterion object that is a logical negation of its SelectionCriterion parameter. A Not criterion returns true for a collection item if Not's component SelectionCriterion expression is false for the item; otherwise it returns true.

The collection searching method that makes use of this SelectionCriterion specifies:

  • Whether to return the first item or item number or all items that satisfy the selection criterion.
  • Where in the collection to begin searching.


%selectionCriterion = [%(SelectionCriterion For itemType):]Not( selectionCriterion)

Syntax terms

%selectionCriterion A SelectionCriterion object variable to contain the new object instance.
[%(SelectionCriterion For itemType):] This optional specification of the class in parentheses denotes a virtual constructor. See "Usage notes", below, for more information about invoking a SelectionCriterion virtual constructor.
selectionCriterion A SelectionCriterion object.

Usage Notes

  • As described in "Virtual Constructor methods", Not can be invoked with no method object, with an explicit class specification, or with an object variable of the class, even if that object is Null:

    %selCrit = Not(criterion) %selCrit = %(SelectionCriterion for float):Not(criterion) %selCrit = %selCrit:Not(criterion)

    Note: As shown in the second of these above, if you explicitly specify the class name, you must include the item datatype of the collection to be searched, just as on a SelectionCriterion object variable's declaration.

  • The Not constructor is never necessary, and anything you can do with the Not can be done (probably more clearly) otherwise. For example, the following two criteria are identical:

    %sel = not(gt(this(90)) %sel = le(this(90))

    And the following two criteria are identical:

    %sel = not(or(lt(this,70), ge(this,95))) %sel = and(ge(this,70), lt(this,95))

    And these criteria are identical:

    %sel = not(true) %sel = false

    Internally, Nots are always converted to the inverse of the parameter criterion.

See also