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Re: Rule of order for dot operators?

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Date Tue, 19 May 2015 16:25:35 +1000
Subject Re: Rule of order for dot operators?
From Chris Angelico <rosuav@gmail.com>
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On Tue, May 19, 2015 at 12:43 PM, Ron Adam <ron3200@gmail.com> wrote:
> Having just implementing something similar for nested scopes, it turns out
> it can't be operators because if it was, then the names y and z would be
> resolved in the wrong scope.
>
>          y = "m"
>          z = "n"
>          a = x . y . z
>
> Which of course wouldn't do what we want.
>
>          a = x . "m" . "n"
>
> And most likely this would give an error.

If you want to implement the dot as an operator, you could do it by
having a special syntactic element called an "atom", which is used for
these kinds of identifier-like tokens. The dot operator could then
take an object and an atom, and effectively return getattr(obj,
stringify(atom)). I'm fairly sure this would result in the same syntax
as Python uses.

ChrisA

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Re: Rule of order for dot operators? Cameron Simpson <cs@zip.com.au> - 2015-05-19 08:29 +1000
  Re: Rule of order for dot operators? Rustom Mody <rustompmody@gmail.com> - 2015-05-18 18:32 -0700
    Re: Rule of order for dot operators? Ron Adam <ron3200@gmail.com> - 2015-05-18 22:43 -0400
    Re: Rule of order for dot operators? Chris Angelico <rosuav@gmail.com> - 2015-05-19 16:25 +1000
    Re: Rule of order for dot operators? Ron Adam <ron3200@gmail.com> - 2015-05-19 14:02 -0400
  Re: Rule of order for dot operators? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-06-08 11:21 +0000
    Re: Rule of order for dot operators? Steven D'Aprano <steve@pearwood.info> - 2015-06-08 23:06 +1000

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