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[0x517A5D]

Doesn't this waste/use a silly amount of blutricity due to the motor losing all of its charge each time you break it?

What?  No!  You never break the motor.  You deploy and break a single frame, that the motor pushes against.

[dragonshardz]

Happy shipbuilding, dragonshardz!

Thanks, this is more than enough to get me started.

[Sergius]

Did they fix those FORTH words that didn't do what they were supposed to?

[MagmaMcFry]

Doesn't this waste/use a silly amount of blutricity due to the motor losing all of its charge each time you break it?

What?  No!  You never break the motor.  You deploy and break a single frame, that the motor pushes against.

That shouldn't really work. You can't make a motor move itself, so if you only ever use one motor, that motor eventually gets left behind.

The toggle between infix-notation compile and postfix-notation execute trips me up, the little fact that parameters are on a different stack than return addresses (except when they're not!) messes with my mind, even stuff like IF and THEN being postfix but ELSE being infix...

Maybe you can't write Forth because you think all those things. Infix notation? Return stack? That stuff isn't even necessary to do something in Forth.
The if/else/then is insanely simple too. The IF pops a value and jumps to after ELSE if the value is zero (or to THEN if ELSE doesn't appear). The ELSE jumps to after THEN. The THEN does nothing.

[0x517A5D]

What?  No!  You never break the motor.  You deploy and break a single frame, that the motor pushes against.

That shouldn't really work. You can't make a motor move itself, so if you only ever use one motor, that motor eventually gets left behind.

Damnit.  That is how motors work, now that I think about it.

I thought I had this working.  I guess I should downgrade a copy of Minecraft, fire up my RP2 world, and see what I did.  Maybe I'm just wrong here.

The toggle between infix-notation compile and postfix-notation execute trips me up, the little fact that parameters are on a different stack than return addresses (except when they're not!) messes with my mind, even stuff like IF and THEN being postfix but ELSE being infix...

Maybe you can't write Forth because you think all those things. Infix notation? Return stack? That stuff isn't even necessary to do something in Forth.
The if/else/then is insanely simple too. The IF pops a value and jumps to after ELSE if the value is zero (or to THEN if ELSE doesn't appear). The ELSE jumps to after THEN. The THEN does nothing.

I know how the IF/ELSE/THEN keywords work.  As far as the textbook goes, the abstract definition.  The problem is, I have to think about what they're going to do, how they're going to affect the rest of the operators every time I encounter them, whether I'm reading or writing code.  Which takes me a couple of seconds of mental effort, and becomes another fact I have to remember about the chunk of code I'm analyzing.

The whole language is full of these issues.  It is not insanely simple.  Not to me.

As for parameter stack vs. return stack, I'm just used to the paradigm where a function is passed some parameters, and consumes them, and maybe returns something.  I can visualize that effortlessly.  I can't do that with FORTH's model.

[MagmaMcFry]

The toggle between infix-notation compile and postfix-notation execute trips me up, the little fact that parameters are on a different stack than return addresses (except when they're not!) messes with my mind, even stuff like IF and THEN being postfix but ELSE being infix...

Maybe you can't write Forth because you think all those things. Infix notation? Return stack? That stuff isn't even necessary to do something in Forth.
The if/else/then is insanely simple too. The IF pops a value and jumps to after ELSE if the value is zero (or to THEN if ELSE doesn't appear). The ELSE jumps to after THEN. The THEN does nothing.

I know how the IF/ELSE/THEN keywords work.  As far as the textbook goes, the abstract definition.  The problem is, I have to think about what they're going to do, how they're going to affect the rest of the operators every time I encounter them, whether I'm reading or writing code.  Which takes me a couple of seconds of mental effort, and becomes another fact I have to remember about the chunk of code I'm analyzing.

The whole language is full of these issues.  It is not insanely simple.  Not to me.

As for parameter stack vs. return stack, I'm just used to the paradigm where a function is passed some parameters, and consumes them, and maybe returns something.  I can visualize that effortlessly.  I can't do that with FORTH's model.

Maybe you aren't thinking about Forth in the right way?

Spoiler: *barfs lesson* (click to show/hide)

A Forth command is executed by executing all the words in the command one after the other, from left to right. The postfix notation is merely a direct result of that. Here's an example:

Code: [Select]

3 2 +The "3" pushes a 3 on the stack. The "2" pushes a 2 on the stack. The "+" pops two values and pushes the sum of those. All three words together have the combined effect of pushing a 5 on the stack.
Notice that the three words don't have to go on the same line. It works just fine like this too:

Code: [Select]

3
2 +Note that the meaning of the second line is "Increment the top stack element by 2".
Let's combine this second line into one word:

Code: [Select]

: IncBy2 2 + ;
The colon indicates the definition of a word, the IncBy3 denotes the name of the new word, and the semicolon denotes the end of the definition.
So now all the following lines have the same meaning:

Code: [Select]

5
3 2 +
3 IncBy2
1 IncBy2 IncBy2
You can visualize IncBy2 as a function with one parameter and one return value. Usage: Put all the parameters onto the top of the stack, then call the function, then the top of the stack is the return values.
By the way, here's a reference for all MineOS commands.
Advanced example:

Code: [Select]

: SumProd OVER OVER * -ROT + ;
This function takes two arguments and returns their sum and product. In Forth terms, this word replaces the first two stack values with their sum and product.
Example:

Code: [Select]

3 4 SumProd . .
This prints 7 and 12. Here's how it works in detail: This is our stack at the start of the program.

Code: [Select]


Note that it's empty. Now 3 is called.

Code: [Select]

3The stack contains a 3 now. The 4 is called subsequently.

Code: [Select]

3 4The stack contains a 3 and a 4. Note that the 4 is on top. Now SumProd changes the stack to:

Code: [Select]

12 7A . is called and displays the output 7 (which is also removed from the stack).

Code: [Select]

12Finally, the other . is called and displays the output 12. The stack is empty again.

Now if you were wondering how exactly SumProd changes the stack, look no further:
The SumProd needs two function arguments (also known as stack elements) to work correctly. Let's make them 3 and 4, as in the previous example.

Code: [Select]

3 4The first word of SumProd is an OVER, which takes the second-to-top stack element and pushes a copy of that onto the stack.

Code: [Select]

3 4 3The second word is another OVER.

Code: [Select]

3 4 3 4Now there's a *. It takes the topmost elements and replaces them by their product.

Code: [Select]

3 4 12The next word is -ROT. It moves the topmost stack element under the next two.

Code: [Select]

12 3 4Finally, the + is called, replacing the topmost two elements by their sum.

Code: [Select]

12 7And that was all there really is to it.

[0x517A5D]

Maybe you aren't thinking about Forth in the right way?

[TL;DR]

Yeah, whatever.

Listen, I have a copy of Brodie's Starting FORTH.  I've read it twice at least, worked through the exercises.  I have the docs for polyFORTH, which I've read in part and skimmed the rest.  I have some other random stuff, like FIG-FORTH for Apple ][.

I've been there, done that.

It didn't work out.

I'm not going to make the effort again.

So evangelize at someone else, okay?

[MagmaMcFry]

So evangelize at someone else, okay?

This is why I made the effort to write up all of that, and also why I posted it here instead of in the programming thread: so all those other people in this thread can finally do something with the 63EL08.

[frostshotgg]

I'm staying out of the FORTH discussion, I said my piece and I agree with whoever said to move to the coding/programming thread.
For whoever asked for a BASIC boot disk, http://ibm5100.net/redpower/basic/

[0x517A5D]

I'm staying out of the FORTH discussion, I said my piece and I agree with whoever said to move to the coding/programming thread.
For whoever asked for a BASIC boot disk, http://ibm5100.net/redpower/basic/

That was me who asked.  Thank you.


Edit: the technique I had described for getting around inchworm mechanisms doesn't work.  I looked at at the quarry machine I had semi-working in my RP2 world, and it was basically extending/retracting a gantry from a fixed point.  I was doing 'arbitrary' movement by manually placing a motor to push the whole machine, which is not what you want for a craft.  I've edited my original post.  Sorry to mislead anyone.

[Sergius]

The trick is managing to convince a server admin to upload your BASIC image, heh.

I think someone even managed to make a C compiler for the 65EL02 (what's a 63EL08?), but you end up with a binary every time so it's pretty much impossible to copy to a SMP server without file access...

Obviously it's fine for single player.

[forsaken1111]

So is it weird that I learned FORTH by watching two 20 minute youtube videos of someone playing minecraft then reading a short document? I make all of my frame machines with the RP computers and its really pretty easy.

[ank]

So is it weird that I learned FORTH by watching two 20 minute youtube videos of someone playing minecraft then reading a short document? I make all of my frame machines with the RP computers and its really pretty easy.

I have not touched logic circuit(outside of simple timers) since I started using RP computers.
FORTH does take a bit of getting used to, but that's mostly the reverse polish notation.
It actually helps a lot if you think about it as an MTG stack.

[DrPoo]

Wouldnt it be possible to make a FORTH program that overwrites part of a sector on a disk?
I mean, it should be possible to push machine code into a place in memory, kinda making an assembler thingie.
Just place some code in the boot sector of the disk so it jumps to the assembled code or some shit.
Should very well be possible.

[TolyK]

So is it weird that I learned FORTH by watching two 20 minute youtube videos of someone playing minecraft then reading a short document? I make all of my frame machines with the RP computers and its really pretty easy.

I have not touched logic circuit(outside of simple timers) since I started using RP computers.
FORTH does take a bit of getting used to, but that's mostly the reverse polish notation.
It actually helps a lot if you think about it as an MTG stack.

Thank. You.