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Comment by hugh | Hacker News Reader

Wait, you couldn't stand the weirdness of perl, but you like Tcl?

All I can remember about Tcl from my months of using it is the ugly, ugly loops:

  for {set i 1} { $i <= 100 } { incr i } {
   puts "Well, that wasn't ugly syntax!"
  }

Incidentally, Fortran, for all its other ugliness, has the best for loop I know:

  do i = 1, 100
   write(*,*) "Hooray, Fortran!"
  enddo

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Tcl is extremely straightforward once you figure it out:

http://antirez.com/articoli/tclmisunderstood.html

'for' is a command that takes 4 arguments:

    {set i 1} - eval'ed once at start time.
    { $i <= 100 } - an expression that is checked each time to determine whether to continue
    { incr i } - eval'ed each time
    { ... the rest ... } the body is eval'ed each time.

Everything in Tcl is like that - it's extremely easy to figure out and there are no surprises. It's also extremely easy to implement. Here's Hecl's for loop:

    case FOR:
    /* The 'for' command. */
    /* start */
    interp.eval(argv[1]);
    /* test */
    while (Thing.isTrue(interp.eval(argv[2]))) {
	try {
	    /* body */
	    interp.eval(argv[4]);
	} catch (HeclException e) {
	    if (e.code.equals(HeclException.BREAK)) {
		break;
	    } else if (e.code.equals(HeclException.CONTINUE)) {
	    } else {
		throw e;
	    }
	}
	/* next */
	interp.eval(argv[3]);
    }
    break;

> Incidentally, Fortran, for all its other ugliness, has the best for loop I know:

How is that better than Python?

    for i in range( 1, 100 ):
        print "Python!"

That's not a good idiom, because it only allows you to loop over small ranges:

  >>> for i in range(1000000000):
  ...     print i
  ... 
  python2.4(1261) malloc: *** vm_allocate(size=4000002048) failed (error code=3)
  python2.4(1261) malloc: *** error: can't allocate region
  python2.4(1261) malloc: *** set a breakpoint in szone_error to debug
  Traceback (most recent call last):
    File "<stdin>", line 1, in ?
  MemoryError

Why attempt to allocate such a large list when you just want to do something several times?

for i in xrange(1000000000): print i

xrange() addresses the problem you describe and has been in Python since, like, forever. However, range() is nicer for learning the language, since it's easy to see how it composes into a list.

Yes, I know. It's just bad that people are taught one way of iterating, and then may or may not learn the right way at some later time.

Ruby's nice and compact too:

    (1..100).each do
      puts "Ruby"
    end

Maybe it's just me, but I like doing it this way in Ruby:

   100.times { puts "Ruby" }

Not that there's anything wrong with your approach, but I just like the way that my code reads almost like English.

Eleven characters! Beats Fortran by four. We have a winner!

(Counting only the loop-related characters, leaving out whitespace.)

Unless anyone has a shorter way of doing something one hundred times?

I think if you want to talk about advantages though, with Fortran you're going to want to talk about the speed, not the brevity. Ruby is quite poky by comparison.

Oh, for sure, but I'd hate to get drawn into the world's Nth general discussion of the advantages and disadvantages of programming languages. That would be dull.

Actually, compared to batty discussions of economics or "politics!!!!!!", it's kind of soothing.

Well, it's shorter by five characters, and you can type it without touching the shift key.

Look, I'm only too familiar with the annoyances of Fortran, but let's allow it this one thing, okay?

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