The Problem with Implicit Scoping in CoffeeScript
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The Problem with Implicit Scoping in CoffeeScript
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Re: The Problem with Implicit Scoping in CoffeeScript
#2Scheme got this right in 1970. There is no excuse to design a new language this way.
Re: The Problem with Implicit Scoping in CoffeeScript
#3CoffeeScript's approach toward top-level variables is quite elegant and simple. When you declare a variable at top-level scope, it is equally available to all code within that file for both reading and writing, with no strange "nonlocal" or ":=" syntax to complicate manners.
Once you understand the reach of CoffeeScript's top-level variables, it is easy to write bug-free code. Since you know that top-level variables have wide scope, you simply need to be judicious about putting variables at top-level scope. If a variable is not needed at top level scope, don't put it there.
Re: The Problem with Implicit Scoping in CoffeeScript
#4CoffeeScript's approach toward top-level variables is quite elegant and simple. When you declare a variable at top-level scope, it is equally available to all code within that file for both reading and writing, with no strange "nonlocal" or ":=" syntax to complicate manners. Once you understand the reach of CoffeeScript's top-level variables, it is easy to write bug-free code. Since you know that top-level variables…
Way to miss the issue. I was not suggesting ":=" for global variables at all. I was suggesting ":=" as a replacement for the nonlocal keyword that Python 3 has to solve the issue I was demonstrating.
Re: The Problem with Implicit Scoping in CoffeeScript
#5Scheme got this right in 1970. There is no excuse to design a new language this way.
I agree with this wholeheartedly--Scheme use an extremely simple scoping model that is nonetheless more expressive than Python (before 3, I guess) and CoffeeScript's. In fact, I only really completely understood JavaScript's model--and realized that, even if a little awkward, it was fundamentally elegant--after writing a Scheme interpreter.
Re: The Problem with Implicit Scoping in CoffeeScript
#6@mitsuhiko Not gonna happen ;) Forbidding shadowing altogether is a huge win, and a huge conceptual simplification.
How arrogant! You'd think he'd step back for a second and consider the suggestion, but it sounds like he's on autopilot.
Re: The Problem with Implicit Scoping in CoffeeScript
#7CoffeeScript's approach toward top-level variables is quite elegant and simple. When you declare a variable at top-level scope, it is equally available to all code within that file for both reading and writing, with no strange "nonlocal" or ":=" syntax to complicate manners. Once you understand the reach of CoffeeScript's top-level variables, it is easy to write bug-free code. Since you know that top-level variables…
Way to miss the issue. I was not suggesting ":=" for global variables at all. I was suggesting ":=" as a replacement for the nonlocal keyword that Python 3 has to solve the issue I was demonstrating.
Nope, I get it, you were suggesting ":=" as a replacement for the "nonlocal" keyword in Python. I'm not sure how my comments demonstrate any lack of reading comprehension. All I said about ":=" and "nonlocal" is that they are overly complicated once you accept that top-level variables can have wide scope.
Obviously, plenty of folks managed to write bug-free code in Python before "nonlocal" was invented. I'm not saying it's a bad idea, but you can avoid bugs without it.
Re: The Problem with Implicit Scoping in CoffeeScript
#8Earlier quoted context omitted.
Way to miss the issue. I was not suggesting ":=" for global variables at all. I was suggesting ":=" as a replacement for the nonlocal keyword that Python 3 has to solve the issue I was demonstrating.
Nope, I get it, you were suggesting ":=" as a replacement for the "nonlocal" keyword in Python. I'm not sure how my comments demonstrate any lack of reading comprehension. All I said about ":=" and "nonlocal" is that they are overly complicated once you accept that top-level variables can have wide scope. Obviously, plenty of folks managed to write bug-free code in Python before "nonlocal" was invented. I'm not sayin…
> Obviously, plenty of folks managed to write bug-free code in Python before "nonlocal" was invented.
Python has the inverse behavior of CoffeeScript. So that was never an issue.
Re: The Problem with Implicit Scoping in CoffeeScript
#9Kind of a side note to the posting, but I just have to say: Please make your usage of parens consistent. If you aren't going to use them, don't use them everywhere.
Here is an example of what I'm talking about:
if isAir cx, cy, cz + 1 then addPlane('near', block)
Should be:
if isAir cx, cy, cz + 1 then addPlane 'near', block
Personally, I use them everywhere because I like having the stronger visual clue that this is a method I'm calling. I think making them optional in CS was a bad idea.
if isAir(cx, cy, cz + 1) then addPlane('near', block)
imho, so much more readable.
Re: The Problem with Implicit Scoping in CoffeeScript
#10@mitsuhiko Not gonna happen ;) Forbidding shadowing altogether is a huge win, and a huge conceptual simplification. How arrogant! You'd think he'd step back for a second and consider the suggestion, but it sounds like he's on autopilot.
It sounds like he had 140 characters to succinctly say what he wanted to say.