TOPS-20 PASCAL Language Manual - Bitsavers

PROCEDURES AND FUNCTIONS
variable section
declares local v~riables.
procedure-and-function section
declares local procedures and functions.
s ta temen t
specifies
procedure
5.
an action to be performed by the procedure. A
can contain any of the statements described in Chapter
A procedure consists of a heading and a block. The procedure block is
similar in structure and contents to the main program block, with the
following exceptions:
• The declaration section cannot contain VALUE initializations.
• The procedure block ends with END followed by a semicolon
(i), rather than a period (.) as in the main program. The
procedure does not have a block if it is a forward
declaration or is defined externally (EXTERNAL or FORTRAN).
You must declare all the variables that are local to the procedure,
but you should not redeclare the formal parameters or the procedure
identifier as variable, type, or constant identifiers.
For the two examples that follow, assume that these declarations have
been made:
CONST NUMBER = 20;
TYPE Range = 0 •• 100;
List = ARRAY[l •• NUMBERJ OF Ran~e;
VAR ARF~
Example 1
: List;
Min i IlIU Ill' M
Ave T'age : r~EAI...;
a ~·d III u tTl
PROCEDURE READ_WRITE (VAR A List);
VAR I : INTEGER;
BEGIN
WRITELN ('Type a list of 20 integers',
'in the range of 0 to 100.');
FOR I := 1 TO Number DO
BEGIN
READCA[IJ);
WRITE(A(IJ!7);
WRITELN
END
END;
The procedure READ WRITE reads a list of
into the array A,-and writes the array.
parameter, the array A.
20 integers, inserts them
READ WRITE uses one variable
Given the declaration of ARR, the following is a valid procedure call:
READ_WRITECARR);
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