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publicdebates • today at 4:51 PM • 1 reply • view on HN

The for loop is odd. Why is the word counter in there twice?

    counter :: int

    for counter in <1, 10-counter> (
       print(counter)
       print(" ")
    )
Using backfor to count backwards is an odd choice. Why not overload for?

    backfor counter in <1, 9> print(counter, " ")
This is confusing to me. Maybe I'm misunderstanding the design principles, but the syntax seems unintuitive.

Replies

briancr • today at 5:48 PM

Yeah this is why the syntax is customizable.. maybe it’s not optimal.

The example I gave was strange and I’ll have to change it. Not sure what I was trying to show there. The basic syntax is just:

for counter in <1, 5> print(counter)

backfor counter in <1, 5> print(counter)

It’s not overloaded because ‘for’ is basically a macro, expanding to ‘iterate, increment counter, break on counter > 5’ where ‘>’ is hard-coded. If ‘for’ was a fundamental operator then yes, there would be a step option and it would be factored into the exit condition.

You’ve got me thinking, there’s probably a way to overload it even as a macro.. hmmm…