Qbasicnews.com

Pages: 1 2 3

Pardon my English for English is not my first language.

Now...

Is structured programming bloatware?
Below are five code samples each doing the same thing.

Samples 1 & 2 are structured, sample 1 using IF...THEN...ELSE,
sample 2 uses SELECT CASE.

The rest is of the unstuctured type designed to run in
GWBASIC for that matter.
Just ingnore the line numbers and replace them with lables
were needed.

In my view sample #3 is good while #4 is bordering on the
unreadeble if a long program is written that way.
I would never program like the #4 is written.

#5 while possible is just plain ridicilous.

Of the #1 & #2 then #2 has an edge over #1 but since this
is just a comparison between two choicies (LEFT & RIGHT) some
might disagree.

However this is not the real dilemma.
The real dilemma is the choice between sample #2 & sample #3.

#3 is much more manageble while #2 is all over the place.
On the other hand #2 has the upper hand of
being *ahem* structured.

Now pick your favourite and just ingnore the line numbers and
replace them with lables were needed.

And here is the code.
It moves the letter 'A' left and right on screen.

Sample #1:

Code:
' Init constants

CONST FALSE = 0, TRUE = NOT FALSE

CONST ESC = 27

CONST LEFT = 1, RIGHT = 2

' Init screen

SCREEN 0, 1, 0, 0

WIDTH 80, 25

CLS

LOCATE 1, 1, 0, 7, 8

' Init variables

Hor% = 41

Vert% = 12

Direction% = RIGHT

ExitProg% = FALSE

TimeDelay! = .1

' Main loop

DO

        LOCATE Vert%, Hor%

        PRINT "A";

        LOCATE Vert%, Hor%

        IF Direction% = LEFT THEN

                Hor% = Hor% - 1

                IF Hor% = 1 THEN Direction% = RIGHT

        ELSEIF Direction% = RIGHT THEN

                Hor% = Hor% + 1

                IF Hor% = 80 THEN Direction% = LEFT

        END IF

        ' Delay loop and exit handler

        T! = TIMER + TimeDelay!

        IF T! > 86399 THEN T! = T! - 86399

        DO

                IF INKEY$ = CHR$(ESC) THEN

                        ExitProg% = TRUE

                        EXIT DO

                END IF

        LOOP UNTIL T! < TIMER

        IF ExitProg% = TRUE THEN EXIT DO

        PRINT " ";

LOOP

' End of program

CLEAR

CLS

END

Sample #2:

Code:
' Init constants

CONST FALSE = 0, TRUE = NOT FALSE

CONST ESC = 27

CONST LEFT = 1, RIGHT = 2

' Init screen

SCREEN 0, 1, 0, 0

WIDTH 80, 25

CLS

LOCATE 1, 1, 0, 7, 8

' Init variables

Hor% = 41

Vert% = 12

Direction% = RIGHT

ExitProg% = FALSE

TimeDelay! = .1

' Main loop

DO

        LOCATE Vert%, Hor%

        PRINT "A";

        LOCATE Vert%, Hor%

        SELECT CASE Direction%

        CASE LEFT

                Hor% = Hor% - 1

                IF Hor% = 1 THEN Direction% = RIGHT

        CASE RIGHT

                Hor% = Hor% + 1

                IF Hor% = 80 THEN Direction% = LEFT

        END SELECT

        ' Delay loop and exit handler

        T! = TIMER + TimeDelay!

        IF T! > 86399 THEN T! = T! - 86399

        DO

                IF INKEY$ = CHR$(ESC) THEN

                        ExitProg% = TRUE

                        EXIT DO

                END IF

        LOOP UNTIL T! < TIMER

        IF ExitProg% = TRUE THEN EXIT DO

        PRINT " ";

LOOP

' End of program

CLEAR

CLS

END

Sample #3:

Code:
SCREEN 0, 1, 0, 0: WIDTH 80, 25: CLS : LOCATE 1, 1, 0, 7, 8

TimeDelay! = .1

Hor% = 41

Vert% = 12

Direction% = 2

LOCATE Vert%, Hor%

PRINT "A";

LOCATE Vert%, Hor%

IF Direction% = 1 THEN Hor% = Hor% - 1: IF Hor% = 1 THEN Direction% = 2: GOTO 110

IF Direction% = 2 THEN Hor% = Hor% + 1: IF Hor% = 80 THEN Direction% = 1

T! = TIMER + TimeDelay!

IF T! > 86399 THEN T! = T! - 86399

IF INKEY$ = CHR$(27) THEN GOTO 170

IF T! > TIMER THEN GOTO 130

PRINT " ";

GOTO 60

CLEAR : CLS : END

Sample #4:

Code:
SCREEN 0, 1, 0, 0: WIDTH 80, 25: CLS : LOCATE 1, 1, 0, 7, 8

TimeDelay! = .1: Hor% = 41: Vert% = 12: Direction% = 2

LOCATE Vert%, Hor%: PRINT "A"; : LOCATE Vert%, Hor%

IF Direction% = 1 THEN Hor% = Hor% - 1: IF Hor% = 1 THEN Direction% = 2: GOTO 60

IF Direction% = 2 THEN Hor% = Hor% + 1: IF Hor% = 80 THEN Direction% = 1

T! = TIMER + TimeDelay!: IF T! > 86399 THEN T! = T! - 86399

IF INKEY$ = CHR$(27) THEN GOTO 90

IF T! > TIMER THEN GOTO 70 ELSE PRINT " "; : GOTO 30

CLEAR : CLS : END

Sample #5:

Code:
SCREEN 0, 1, 0, 0: WIDTH 80, 25: CLS : LOCATE 1, 1, 0, 7, 8: TimeDelay! = .1: Hor% = 41: Vert% = 12: Direction% = 2

LOCATE Vert%, Hor%: PRINT "A"; : LOCATE Vert%, Hor%: IF Direction% = 1 THEN Hor% = Hor% - 1: IF Hor% = 1 THEN Direction% = 2: GOTO 40

IF Direction% = 2 THEN Hor% = Hor% + 1: IF Hor% = 80 THEN Direction% = 1

T! = TIMER + TimeDelay!: IF T! > 86399 THEN T! = T! - 86399

IF INKEY$ = CHR$(27) THEN CLEAR : CLS : END ELSE IF T! > TIMER THEN GOTO 50 ELSE PRINT " "; : GOTO 20

Now pick.
:???:

#1 with 2-space tabs.

Same.

(I'll have to lookup the locate command :o)

#3 with labels.

Quote:#3 with labels.

LOL! 8)
I myself would proberbly pick #1 in a
two choice senario.

Still, I kind of miss the old days.

We'll never understand you, aga....

(Agree with everyone else, tho)

Here's a better choice . . . Smile

[modified]

Code:
SCREEN 0, 1, 0, 0: WIDTH 80, 25: CLS : LOCATE 1, 1, 0, 7, 8 

timeDelay! = .1: horiz% = 41: vert% = 12 

t1! = TIMER + timeDelay!: IF t1! > 86400 THEN t1! = t1! - 86400

direction% = 1

DO 

IF INKEY$ = CHR$(27) THEN EXIT DO 

IF TIMER > t1! THEN 

t1! = TIMER + timeDelay!: IF t1! > 86400 THEN t1! = t1! - 86400

PRINT " "; 

LOCATE vert%, horiz%: PRINT "A"; : LOCATE vert%, horiz% 

IF horiz% = 80 THEN direction% = -direction% ELSE IF horiz% = 1 THEN direction% = -direction% 

horiz% = horiz% + direction% 

END IF 

LOOP

Quote:Here's a better choice . . .

Code:
SCREEN 0, 1, 0, 0: WIDTH 80, 25: CLS : LOCATE 1, 1, 0, 7, 8 timeDelay! = .1: horiz% = 41: vert% = 12 t1! = TIMER direction% = 1 DO IF INKEY$ = CHR$(27) THEN EXIT DO IF ABS(TIMER - t1!) > timeDelay! THEN t1! = TIMER PRINT " "; LOCATE vert%, horiz%: PRINT "A"; : LOCATE vert%, horiz% IF horiz% = 80 THEN direction% = -direction% ELSE IF horiz% = 1 THEN direction% = -direction% horiz% = horiz% + direction% END IF LOOP

OK...

Good points... bad points
The bad points first:

You have:

IF ABS(TIMER - t1!) > timeDelay! THEN
This is one calculation (TIMER - t1!) and
one function (ABS) the comp has to go through constantly
as it executes the main DO...LOOP.
It's slow.

Still, the accuracy of the logic might be better than mine
especally in extreme boundary cases that might occur once in a
blue moon.
This is untested (by me anyhow).

However I loved the play on the positive and the negative
values on direction.
I wonder how to implement this in game engines as far as
readabillity and logic goes.
(I am just beginning looking into game engines and graphics
programming.)

But yeah, nice idea.

P.S.
I forgot to flush the keyboard buffer in the Init section
in my samples.
Damm, perfection is so hard too reach.

#1 or #2. Both are good. The others are not proper form anymore. However, they all should compile to just about the same code. Why you're considering structured programming "bloatware" is beyond me...especially when they all compile to the same thing. Readable sourcecode, whether its larger or not, is going to help your development in the long run. Using line numbers and GOTOs isn't going to give you any speed boosts in this particular case...there are times when it *might* be *slightly* faster to use GOTOs and line numbers or labels, but this isn't one of them.

adosorken:

For the record:
I began my programing on the ZX Spectrum with line numbers
and whatnot.
Then I moved to QBAISC 1.0 and 1.1 (crippleware) and VBDOS.

While programing in VBDOS I got involved with a complex and
large project.
I may have upgraded my BASIC but I didn't upgrade my mentality.

The results where catastrophic and the project came a total mess
whith a very large number of globals for e.x.

Since then I have *HATED* unstuctured programming but
the funny thing is now after some years have passed I
don't see it as totally evil anymore and I still kind of miss the
quick and dirty feel of it.

There is even a case too be made that it is the prefered way
in small projects. (Aga.. Wink Wink!)
And I totally understand that.

However,
you will not catch me *DEAD* using the unstructured way.
I have learnd my lesson.

But there is always the temtation for e.x. when you are doing
Q&D converters or something.

But I stand fast on my commitment.

So there you have it.

Pages: 1 2 3

IceMan

Plasma

oracle

Agamemnus

IceMan

RST

Agamemnus

IceMan

adosorken

IceMan