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0 pointswisty14y ago0 comments

I think Python's is deliberately unexpressive, forcing you to use local variables pretty much everywhere. This tends to decouple stuff, which is usually good. The model is "everything you do is local, unless you know better, and want to jump through a lot of hoops". Coffeescript works a similar way.

Javascript seems to have the model "everything you do is global, unless you know better".

I'm not a big Javascript hater, but this is one very sore point.

0 comments

swannodette14y ago

"everything you do is global, unless you know better"

That is not the JavaScript model at all.

lnanek14y ago

He is talking about if you don't do anything extra (in this case, use the var keyword). Much like the nonlocal keyword in Python requires knowing about it and wanting to use it in order to actually use it and get the non-default behavior.

swannodette14y ago

var is not extra in JavaScript the way nonlocal is in Python. var is a language construct that any good JavaScript program must use.

Lazare14y ago

The point of the linked article is that this is not the CoffeeScript way at all (although the author wishes it was).

whateverer14y ago

No, the Javascript model is "you name things with `var`, you mutate things with `=`".

Python went for a more complicated scheme of having every variable in a function be a new binding when first assigned, and then it's just mutation (i.e. 'local'), unless explicitly declared to be nonlocal, but it still makes sense with their... penchant for mutable state.

And Coffescript instead went over to PHP to have some of the glue it was eating.

Someone14y ago

No, the Javascript model is "you name things with `var`, you mutate things with `=`".

If only it were that simple. It also has "you create thing with `var` and sometimes with `=`", plus it does not have block scope:

    if( true)
    {
       var x = 1;
    }
    // x == 1 here.

ryanflorence14y ago

Functions define scope. The end. Not hard. One rule.

rayiner14y ago

'let' is a way to make things more local! When I say: let x = 0, I'm saying "hey, I don't care what 'x' is in other scopes, in this local scope it's 10, dammit!"

draegtun14y ago

Yes explicit is best and in Perl its very clear what you want...

  my $x = 10;

j / k navigate · click thread line to collapse

0 comments

swannodette14y ago

"everything you do is global, unless you know better"

That is not the JavaScript model at all.

lnanek14y ago

swannodette14y ago

var is not extra in JavaScript the way nonlocal is in Python. var is a language construct that any good JavaScript program must use.

Lazare14y ago

The point of the linked article is that this is not the CoffeeScript way at all (although the author wishes it was).

whateverer14y ago

No, the Javascript model is "you name things with `var`, you mutate things with `=`".

And Coffescript instead went over to PHP to have some of the glue it was eating.

Someone14y ago

No, the Javascript model is "you name things with `var`, you mutate things with `=`".

If only it were that simple. It also has "you create thing with `var` and sometimes with `=`", plus it does not have block scope:

    if( true)
    {
       var x = 1;
    }
    // x == 1 here.

ryanflorence14y ago

Functions define scope. The end. Not hard. One rule.

rayiner14y ago

'let' is a way to make things more local! When I say: let x = 0, I'm saying "hey, I don't care what 'x' is in other scopes, in this local scope it's 10, dammit!"

draegtun14y ago

Yes explicit is best and in Perl its very clear what you want...

  my $x = 10;

j / k navigate · click thread line to collapse