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21 
22 
23 package com.sun.star.report;
24 
25 /**
26  * Functions are statefull computation components.
27  *
28  * Functions are allowed to have a state, but are considered
29  * immutable (the same is true for expressions). Functions are
30  * allowed to update their state on every call to 'advance', which
31  * signals, that the cursor has been moved.
32  *
33  * Functions have no way to 'reset' their state, if a reset is needed,
34  * the report engine is urged to query a new instance from the ReportAddin.
35  */
36 public interface ReportFunction extends ReportExpression
37 {
38 
advance(DataRow row)39     public ReportFunction advance(DataRow row);
40 }
41