Calling Procedures

Learning Objective:

For procedure calls:

a. Write statements to call procedures

b. Determine the effect of the procedure call

AAP-3.A.1

A procedure is a named group of programming

instructions that may have parameters and

return values.

AAP-3.A.2

Procedures are referred to by different names,

such as method or function, depending on the

programming language.

AAP-3.A.3

Parameters are input variables of a procedure.

Arguments specify the values of the

parameters when a procedure is called.

AAP-3.A.4

A procedure call interrupts the sequential

execution of statements, causing the program

to execute the statements within the procedure

before continuing. Once the last statement

in the procedure (or a return statement)

has executed, flow of control is returned to

the point immediately following where the

procedure was called.

AAP-3.A.5

The exam reference sheet provides

procName(arg1, arg2, ...)

as a way to call

Text:

PROCEDURE procName(parameter1,

parameter2, ...)

{

<block of statements>

which takes zero or more arguments; arg1

is assigned to parameter1, arg2 is

assigned to parameter2, and so on.

The exam reference sheet provides the

procedure

Text:

DISPLAY(expression) to display the value of expression, followed

by a space.

The exam reference sheet provides the

Text:

RETURN(expression) statement, which is used to return the flow

of control to the point where the procedure

was called and to return the value of

expression.

The exam reference sheet provides

result procName(arg1,

arg2, ...)

to assign to result the “value of the

procedure” being returned by calling

Text:

PROCEDURE procName(parameter1,

parameter2, ...)

{

<block of statements>

RETURN(expression)

AAP-3.A.9

The exam reference sheet provides procedure

Text:

INPUT()

Block:

INPUT

which accepts a value from the user and

returns the input value.