f



why "::", not "."

Why does the method of modules use a dot, and the constants a double
colon?
e.g.
Math::PI and Math.cos

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10/26/2010 8:48:05 AM
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On Oct 26, 2010, at 01:48 , Oleg Igor wrote:

> Why does the method of modules use a dot, and the constants a double
> colon?
> e.g.
> Math::PI and Math.cos

For the same reason why inner-classes/modules use double colon, because =
they're constants and that's how you look up via constant namespace.

Math::PI and ActiveRecord::Base are the same type of lookup... it is =
just that Base is a module and PI is a float.

You can also use double-colon for invocation:

% ruby -e 'p Math::exp(1)'
2.71828182845905

but that is frowned upon as non-idiomatic ruby.



0
Ryan
10/26/2010 9:24:35 AM
On Tue, Oct 26, 2010 at 5:24 AM, Ryan Davis <ryand-ruby@zenspider.com> wrote:

> You can also use double-colon for invocation:
>
> % ruby -e 'p Math::exp(1)'
> 2.71828182845905
>
> but that is frowned upon as non-idiomatic ruby.

Not so much non-idiomatic as archaic.

Kind of like using thee and thou, or goeth (as in "Pride goeth before
the fall") in modern English. <G>


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rick.denatale (1691)
10/26/2010 3:10:07 PM
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