Monday, January 20, 2014

The IDE called Forth, or.. Forth I wish I knew how to quit you.

I've been playing with OpenFirmware. Yep, booting it off of a thumb drive (via Grub2). It takes less than a second to boot on a "fast" laptop up to the Forth "ok" prompt.  At that point, I can start playing around with low level hardware.  Open Firmware went so far as to provide a "GNU readline" like capability where I can use Emacs-like command line editing and completion of words.

But, wait, there is no command manual!  What does this word do?  Enter "see" and the word you are interested in and view disassembled source code.

People (still) underestimate the innovations built into a "classic" Forth.   Gforth still has some classic capability built in.

Here is what I had with Forth during the 1980s (on Commodore 64 and then Atari ST):
  1. Full screen block editor.
  2. "See" or equivalent for looking at source.
  3. The ability to ask the block editor to locate the "real" source and let me edit it (i.e. Tags).
  4. The ability to play around with graphics and other hardware facilities.
  5. Very fast start up (or restart for when I crash the machine).
This was the basic Forth IDE.

I'm a long time Emacs user (25+ years)  and I still not at that same IDE productivity level I was with Forth back in the day.

Smalltalk (in particular Squeak) has been the only other things that has come as close (for me).

I know that machines are bigger and software is a lot more complex these days, but why can't I have that same feeling of "being one" with the machine?

Here is what I want:  I want to load up an interesting library (e.g. libpcap, OpenCV, etc) into a Forth (e.g. Gforth) and explore.  I want to play.  Lua, Perl and Python can get me half way there (i.e. bindings), but I still have to grapple with a REPL that doesn't seamlessly integrate with the editor.  

Yes, yes I know you can bend Vim or Emacs to do these things, but the resulting IDE isn't as natural (IMHO). You are still piecing together a generic editor, a command line (linux shell) and a programming language. (For example, how do you list a directory in the chosen language? Oh, you use the shell or editor? Are the results first class elements for the language?). 

Some would say that Visual Studio is a great example of a seamless IDE, but it is still working with a language that isn't naturally "interactive".

This is why I still hang onto Forth. It isn't about Forth building better apps. I don't care what an app is built in.   It isn't about the destination, its all about the journey.

Thursday, January 02, 2014

Todd's 1 question test for all new "advanced" dynamic scripting/programming languages.

Whenever a new language comes out I have a simple test to see if it is worth looking at.  I came up with this test back in the 1990s after being frustrated by the state of "advanced programming languages".

In the 1980s, as a lowly FORTH programmer, twiddling 8-bit bytes, I was blown away with my first experience with Lisp. It was on a DEC2060 (running TOPS-20) and was called "Standard Lisp".

As a student, back in 1984, I coded up a small lisp function to compute the factorial of 120.

The terminal presented me with:


My mind was sufficiently blown.

Of course, the largest factorial computed by a programming language where the number/integer type is matched to the machine word size is much smaller.  I had already programmed in Pascal, FORTH, a bit of C and BASIC.  But, this was the first language implementation I had seen that wasn't bound by that machine word limitation.

(I quickly followed that exercise by coding for the factorial of increasing numbers until, by the time I was in the hundreds of thousands, the terminal responded with a message saying that it was taking too many resources and that the process was being "spooled" -- whatever that meant.  I went home and the next morning I was greeted with an email from the sysadmin requesting that I come get a "print job" from the ops center.  I rang the ops center door buzzer, the admin came to the door and asked what I wanted. I told him him who I was and he then frowned, told me to wait and closed the door. A few minutes later he showed up with a hand truck loaded with a big box of green bar printer paper.  Apparently, "spooled" meant the result was being submitted as a print job).

A couple of years later and I discovered that Smalltalk too had this "big num" (or arbitrary precision) feature.  Why wouldn't every language have that? (Yeah, I know... performance...but, still...)

Now, when I am presented with a programming language that is supposed to be the "next step",  I look to see if it supports bignum.  Now, when I say support, I don't mean surrounding the number by quotes and submitting it to a bignum library. That's cheating. I want to say something like:

X=6689502913449127057588118054090372586752746333138029810295671352301633557244962989366874165271984981308157637893214090552534408589408121859898481114389650005964960521256960000000000000000000000000000  / 19;

I don't want to type it as a string. That's saying that there is something "special" or "hard" about large numbers.  Why, in 2014, should I be concerned about whether a number fits into 32 or 64 bits (or in the case of Lua and Javascript: a 52 bit mantissa)?  I want tnative/natural support.

So, what other programming languages pass this bignum test?

  • Erlang does. 
  • Haskell does... sort of... got to choose the right type.
  • Perl does (and has for a while.. just type "use bigum;"  and all following numbers are not bound by machine word size.

Now, don't get me going about native/natural support for rational types.