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| <span style="font-size:120%; color:black"><b><section begin=dpl_desc/>Return n<section end=dpl_desc/></b></span>
| | #REDIRECT [[FindPreviousItemNumber (GenericNamedArraylist function)]] |
| [[Category:UnicodeNamedArraylist methods|FindPreviousItemNumber function]]
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| <!--DPL?? Category:UnicodeNamedArraylist methods|FindPreviousItemNumber function: Return n-->
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| <p>
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| FindPreviousItemNumber is a member of the [[UnicodeNamedArraylist class]].
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| </p>
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| This function searches “backward” in the UnicodeNamedArraylist to find and
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| return the item number of the next item that matches a specified criterion.
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| The criterion is supplied by the [[SelectionCriterion class|SelectionCriterion]] object
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| that is a required FindPreviousItemNumber parameter.
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| If no item satisfies the criterion,
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| the method returns a zero.
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| ==Syntax==
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| %itemnum = %unamrayl:FindPreviousItemNumber(criterion -
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| [, Start=itemnum])
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| ===Syntax Terms===
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| <dl>
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| <dt><i>%itemnum</i>
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| <dd>A numeric variable to contain the item number of the
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| item that is located by the search.
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| <dt><i>%unamrayl</i>
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| <dd>A UnicodeNamedArraylist object.
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| <dt><i>criterion</i>
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| <dd>A SelectionCriterion object, which is a relational expression that is
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| applied to a ''%unamrayl'' item value to determine
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| whether the value satisfies the expression.
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| The expression consists of a function, an operator, and a User Language intrinsic type
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| (numeric, string, or Unicode) value.
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| For example, <tt>LT(this, 101)</tt> is the
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| criterion <tt>this</tt> <tt><</tt> <tt>101</tt>, where
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| <tt>this</tt> is an identity function that simply returns the item's value.
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| The item number of the first item tested by FindPreviousItemNumber that satisfies
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| this expression is the method's return value.
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| The function in the criterion is
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| a method value (a method or class member name literal, or a method variable)
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| for a method
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| that operates on items of the type specified on the ''%unamrayl''
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| declaration and that returns an intrinsic value.
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| This is described further in "[[SelectionCriterion class#Specifying a SelectionCriterion's parameters|Specifying a SelectionCriterion's parameters]]".
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| <dt><b>Start=</b><i> itemnum</i>
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| <dd>The number of the item ''before'' which to begin the search.
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| If the ''itemnum'' value of Start is 4, item 3 is the first item considered.
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| The value of Start may be 1 through one plus the number of items in
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| the UnicodeNamedArraylist.
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| For a collection of three items, ''itemnum'' may be 1, 2, 3, or 4.
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| This is an optional argument, and it defaults to one plus the number of items in
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| the UnicodeNamedArraylist.
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| If you specify a value, the parameter name <tt>Start</tt> is required.
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| </dl>
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| ==Usage Notes==
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| <ul>
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| <li>If the value of Start is not in the range of 2 through one plus the number
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| of items in the UnicodeNamedArraylist, the request is cancelled.
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| If the value of Start is 1, no item can be found and
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| the method returns a zero.
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| <li>[[FindNextItemNumber (UnicodeNamedArraylist function)|FindNextItemNumber]]
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| is identical to FindPreviousItemNumber except that it searches forward in
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| the UnicodeNamedArraylist.
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| </ul>
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| ==Examples==
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| See the [[FindNextItemNumber (UnicodeNamedArraylist function)#Examples|FindNextItemNumber example]] for an example with a FindPreviousItemNumber call.
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