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Unit 8: Understanding Function and Procedure

End function
The saying “Less is more.” is displayed in the text box.

8.4 Comparing Function Procedures with Sub Procedures

Function Procedures differ from Sub Procedures in the way they are accessed. Sub Procedures are
invoked with call statements, whereas function are invoked by placing them where you would
otherwise expect to find a literal, variable, or expression. Unlike a Function Procedures, a Sub
Procedures can’t be used in an expression.
Function Procedures can perform the same tasks as Sub Procedures. For instance, they can request
input and display text. However, Function Procedures are primarily used to calculate a single
value. Normally, Sub Procedures are used to carry out other tasks.

The Sub Procedures considered in this book terminate only when End Sub is
reached. On the other hand, Function Procedures terminate as soon as the first
Return statement is executed. For instance, if a Return statement is followed
by a sequence of statements and the Return statement is executed, then the
sequence of statements will not be executed.

8.5 Collapsing a Procedures with a Region Directive

A group of Procedures or class-level variables can be collapsed behind a captioned rectangle. This
task is carried out with a so-called Region directive. To specify a region, precede the code to be
collapsed with a line of the form
#Region “Text to be displayed in the rectangle”.
and follow the code with the line
#End Region

Figure 8.1(a): Region Directives.

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