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Python doesn't mandate block structure and indentation in lines within brackets and parens. Ask yourself why is that and you'll have the reason why it makes se
by euccastro 16y ago
Python doesn't mandate block structure and indentation in lines within brackets and parens. Ask yourself why is that and you'll have the reason why it makes sense in Lisp.
I'm very familiar with Python and hack occasionally in Scheme. After a really short time, parens really are no problem. They are an asset. In big functions where indentation stops being obvious at a glance (and in smaller ones, what's the problem?), I can more easily see/check the extent of a block in Scheme (with editor paren matching) than in Python. The editor is better able to help me select and operate on such blocks. Moving blocks around (e.g. for refactoring) is easier, faster and feels safer.
If I still use Python more often than Scheme it has nothing to do with parens. Much on the contrary, that's one of the reasons I wish I could spend more time in Scheme.
- Locke1689 16y agoPython doesn't mandate block structure and indentation in lines within brackets and parens. Ask yourself why is that and you'll have the reason why it makes sense in Lisp. Because they screwed up? I think indentation like the following should be mandatory across multiple lines: fun_a(long_arg_a, long_arg_b, long_arg_c)
- euccastro 16y agoAnd does that remove the need for parentheses? ;) Because actually, it gets more complicated than that. Sometimes it makes more sense to say: def open_window(x, y width, height, resizable=True, caption="") Without parens, is x, y a tuple or two separate arguments? And do I want to remember that? Also, what's inside the parens could have been a generator expression, which could have been conceivably partitioned in more than one sensible way, and which could have subexpressions with parens or brackets itself. Sounds contrived? I do it all the time and it often looks and reads just fine. I'm not arguing against your indentation rule, which is the one I use, and not even against the proposal of making it mandatory (although I'm not sure that in the heat of refactoring I'd appreciate the unnecessary SyntaxErrors), but about the point that making it mandatory would make parens unnecessary.
- Locke1689 16y agoTrue, although Haskell does show we can do function application without excessive parentheses. I think you're definitely right about Python, though. Fundamentally, Python is still a procedural, block style language. If it were written in the same functional style as Lisp it would probably be just as complex.
- silentbicycle 16y agoThe ML and APL families also do function application without excessive parens. I don't think Lisp's grouping rules are complex. There are a few functions with special grouping, particularly let and cond, but anybody doing real programming in Lisp gets used to them pretty quickly. (Lisp is hardly the only language with special cases in its syntax!) User-added functions seldom have elaborate nesting schemes, or at least have a damned good reason.