FindNextItemNumber (GenericNamedArraylist function)

<section begin=dpl_desc/>Return number of matchi<section end=dpl_desc/>

FindNextItemNumber is a member of the NamedArraylist class.

This function searches “forward” in the NamedArraylist to find and return the item number of the next item that matches a specified criterion. The criterion is supplied by the SelectionCriterion object that is a required FindNextItemNumber parameter. If no item satisfies the criterion, the method returns a zero.

FindNextItemNumber is available in Sirius Mods version 7.6 and later.

Syntax

  %itemnum = %namrayl:FindNextItemNumber(criterion        -
                                         [, Start=itemnum])

Syntax Terms

%itemnum

A numeric variable to contain the item number of the item that is located by the search.

%namrayl

A NamedArraylist object.

criterion

A SelectionCriterion object, which is a relational expression that is applied to a %namrayl item value to determine whether the value satisfies the expression. The expression consists of a function, an operator, and a numeric or string value. For example, GT(this, 11) is the criterion this > 11, where this is an identity function that simply returns the item's value. The item number of the first item tested by FindNextItemNumber that satisfies this expression is the method's return value. The function in the criterion is a method value (a method or class member name literal, or a method variable) for a method that operates on items of the type specified on the %namrayl declaration and that returns a numeric or string value. This is described further in "Specifying a SelectionCriterion's parameters".

Start= itemnum

The number of the item after which to begin the search. If the itemnum value of Start is 2, item 3 is the first item considered. The value of Start may be 0 through the number of items in the NamedArraylist. For a NamedArraylist of three items, itemnum may be 0, 1, 2, or 3. This is an optional argument, and it defaults to 0. If you specify a value, the parameter name Start is required.

Usage Notes

• If the value of Start is greater than the number of items in the NamedArraylist, the request is cancelled. If the value of Start is equal to the number of items, FindNextItemNumber returns a zero.
• The FindPreviousItemNumber functional is identical to FindNextItemNumber except that it searches backward in the NamedArraylist.

Examples

In the following fragment, two FindNextItemNumber calls and one FindPreviousItemNumber call are applied to a collection of objects of the staff class that is defined in the request in "NamedArrayArraylist FindPreviousItem function example":

    %old is namedArraylist of object staff
    %old = new
    %old('Jim') = newf('Red', 'employed')
    %old('Jed') = newf('Black', 'retired')
    %old('Jan') = newf('Green', 'employed')
    %old('Jud') = newf('Brown', 'retired')
    %old('Jon') = newf('White', 'retired')

    %sel1 is object selectioncriterion for float
    %sel2 is object selectioncriterion for float
    %n is float
    %sel1 = GT(name, 'Mud')
    %sel2 = AND(GT(name, 'Mud'), EQ(status, 'retired'))

    %n = %old:FindNextItemNumber(%sel1, start=1)
    Print %old:nameByNumber(%n)

    %n = %old:FindNextItemNumber(%sel2)
    Print %old:nameByNumber(%n)

    %n = %old:FindPreviousItemNumber(LT(name, 'Mud'),  -
                                     start=%n)
    Print %old:nameByNumber(%n)

The result is:

    Jim
    Jon
    Jan