const is better for constants, you have be careful with #define/macros
suppose that your define was #DEFINE p2 Pi + Pi then x=p2*4 would become Pi+Pi*4 unless you enclose it in parentheses

He was literally describing a #define, but calling it "EQN". Hence my reply: call it DEFINE or MACRO.

The whole point of a constant is that it can't be modified. The other point is that it's a literal replacement made at compile time.

Let's look at one of list of constants built in to the DotNet SDK, the keyboard scan codes. There are 773 keyboard scan codes in the System.Windows.Forms.Keys enumeration - just for a list of keys on the computer.

Now consider all of the other thousands of enumerations and constants in the system... the "Magic Number Database" has over 380,000. That's not all of them, either. So if you were to include all of the constants your program might need as variables every time you compile it, you would be adding in over 1.5 megabytes just for the variable storage, not to mention the other things that go into storing and retrieving a variable.

So there are two very important reasons to use CONST in your program:
1. It's an obvious semantic flag that says "this value isn't going to change."
2. Those values get converted directly to data during compile time. There's no variable storage or lookup for those values, and unused constants actually disappear from the object code, saving even more space.

Does it matter in a little dinky 30K demo? No. But does it matter in large applications, spanning thousands of source files and multiple megabytes of object code?

Absolutely.

@tomxp411 I could not reproduce the issue regarding breakpoints, so I'd be glad if you could list the exact steps to reproduce it (provide some simple code if you can).

I can't reproduce it on a simple test program, either. I'll try it again the next time I'm working on my Trek program.

Thanks. That helps.

I am not sure if I've actually used QB64 on my Pi. I have been meaning to try it, as I want my programs to work on Linux, as well as Windows. I'll have to remember to start testing on the Pi, once in a while.

Be really cool getting QB64 working on those devices.

I checked out a Pi a couple years ago, the screen was smaller than a phone's, not going to work with old eyes!, I returned the kit and appreciate my laptop all the more!

But that kind of thing is the base of young computer hobbyists for today!

You probably got one of the handheld portable kits. The Pi is designed to use any HDMI display, so you can use it on any modern TV or computer monitor.

I just tried it, and BEEP doesn't seem to actually make a difference. I tried it with my 900 line Trek program, and it takes about 5 seconds to launch (after taking a bit longer the first try that day. I blame a newly booted computer and freshly downloaded source files.)

I placed a BEEP on the first line of code that actually gets executed. It did not change the compile or launch time. Still about 5 seconds.
I took the BEEP back out. Still about 5 seconds.

So I tried another program: a simple 15 line keyboard test utility. Same deal. With or without BEEP, it takes about 4-5 seconds to compile and launch.

How big is your program? Do you have any includes? I'm thinking you are seeing the effects of caching or pre-compilation or some other optimization that takes effect after the first use. BEEP itself does not actually seem to make a difference to me.

Ok, we need to hook up at a bar and have a beer and talk this through.... so you guys are saying the IF is in fact a decision and not a simple ON arriving at the index zero, print the index zero?? The IF statement in your example Steve simply says "IF a", which I have always read "On reaching a " or " If the loop index has reached a .. print it's value"

It seems, even if I make a = 0, which should be a True statement   (ie a = 0  : If a then Print "True" else Print "False" comes up with False)   we don't take away the decisional aspect of "If a"

I appreciate the lesson here. Thanks guys.

You're over-complicating the IF statement.

The IF statement tests for zero. That's all it does. Any other comparisons are actually done by the expression in the IF statement, not IF itself.

IF <value> THEN
<value is not zero>
ELSE
<value is zero>
END IF

IF does not test for equality, greater, lesser, or anything else. It simply checks for zero. In fact, the machine code for this ends up as "Jump if Zero" (JZ) and "Jump if Not Zero" (JNZ).

So everything between IF and THEN is actually an expression., which returns a numeric result.

In BASIC, an expression is basically anything that can be turned into a value: "3" is an expression, "4  + 5" is an expression, and "A < Y" is an expression that returns a Boolean result.

And since a Boolean result is either On or Off, we treat Off as zero and On as -1 (Because signed binary integers are negative when the left bit is on. It's more complicated than that, but that's how the "negative" flag works in machine language.)

So things like IF X=Y are actually two separate operations: the expression (X=Y) is evaluated first and returned as a single value. The IF statement then jumps to the ELSE or END IF when the value is non-zero.

To understand Boolean expressions a bit more, consider these statements:

PRINT 0
PRINT 1
PRINT 0=0
PRINT 0=1
PRINT 1=1

PRINT 0=0 prints -1, because when the = is used in an expression, it's a test for equality. And a test for equality returns -1 when the two values are equal.
Likewise 0=1 returns 0, and 1=1 returns -1

Once you understand the separation between statement and expression, you'll better understand how to use the IF statement to write complex and useful tests.

Looks like your right, though why it cares?
perhaps I have gotten to used to be able to go high to low in things like LINE and _PUTIMAGE?
and it doesn't care if I CASE 16,15,14,13,12,11.
but what ever, found why there was an issue and resolved,
Thanks Steve.

Think about how the TO operator works.  CASE X TO Y is shorthand for
IF Value >= X AND Value <= Y THEN ...

So if you plug your numbers into the test, you get:
IF 15 >= 16 AND 15 <= 11 THEN
What is the result of this test?

The reason it works with a list (16,15,14, etc) is that the value is compared separately against each item in the list. Expressed as an IF, that's:
IF 15 = 16 OR 15 = 15 OR 15 = 14 ...

Does that make sense?