PROCEDURES AND LOCAL VARIABLES
A procedure can declare it's own variables to work with. These variables belong to the procedure in which they are declared. Variables declared inside a procedure are known as local.

Local variables can be accessed anywhere between the begin and matching end keywords of the procedure. The following program illustrates the use and scope (where variables are visible or known) of local variables.

	program LOCAL_VARIABLES (input, output);
	var   number1, number2 : integer;  {these are accessible by all}

	procedure add_numbers;
	var   result : integer;            {result belongs to add_numbers}
	begin
	      result := number1 + number2;
	      writeln('Answer is ',result)
	end;

	begin                              {program starts here}
	      writeln('Please enter two numbers to add together');
	      readln( number1, number2 );
	      add_numbers
	end.

SELF TEST 21: LOCAL VARIABLES
Determine this programs output.

	program  MUSIC (output);
	const SCALE = 'The note is ';
	var   JohnnyOneNote : char;

	procedure Tune;
	const SCALE = 'The note now is ';
	var   JohnnyOneNote : char;
	begin
	      JohnnyOneNote := 'A';
	      writeln(SCALE, JohnnyOneNote )
	end;

	begin
	      JohnnyOneNote := 'D';
	      writeln(SCALE, JohnnyOneNote );
	      Tune;
	      writeln(SCALE, JohnnyOneNote )
	end.

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