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Re: Using the Python Interpreter as a Reference

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On Sun, Nov 27, 2011 at 4:55 PM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
>> My language combines generators and collection initializers, instead of
>> creating a whole new syntax for comprehensions.
>>
>> [| for i in 0..10: for j in 0.10: yield return i * j |]
>
> Are we supposed to intuit what that means?
>
> Is | a token, or are the delimiters [| and |] ?
>
> Is there a difference between iterating over 0..10 and iterating over
> what looks like a float 0.10?
>
> What is "yield return"?

I would assume that "yield return" is borrowed from C#, where it is
basically equivalent to Python's yield statement.  The advantage of
using two keywords like that is that you can compare the statements
"yield return foo" and "yield break", which is a bit clearer than
comparing the equivalent "yield foo" and "return".

Having to type out "yield return" in every comprehension seems a bit
painful to me, but I can understand the approach: what is shown above
is a full generator, not a single "generator expression" like we use
in Python, so the statement keywords can't be omitted.  It's trading
off convenience for expressiveness (a bad trade-off IMO -- complex
generators should be named, not anonymous).

>> Lambdas and functions are the same thing in my language, so no need for
>> a special keyword.
>
> That does not follow. Lambdas and def functions are the same thing in
> Python, but Python requires a special keyword.

I think the implication is that Unit has only one syntax for creating
functions, which is lambda-style.  In any case, why does Python
require a special keyword?  def is only used in a statement context,
and lambda is only used in an expression context.  Why not use the
same keyword for both?  I think the answer is historical:  def came
first, and when anonymous functions were added it didn't make sense to
use the keyword "def" for them, because "def" implies a name being
defined.

Cheers,
Ian

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Using the Python Interpreter as a Reference Travis Parks <jehugaleahsa@gmail.com> - 2011-11-20 16:46 -0800
  Re: Using the Python Interpreter as a Reference Chris Angelico <rosuav@gmail.com> - 2011-11-21 13:33 +1100
    Re: Using the Python Interpreter as a Reference Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-21 05:44 +0000
      Re: Using the Python Interpreter as a Reference Chris Angelico <rosuav@gmail.com> - 2011-11-21 17:48 +1100
      Re: Using the Python Interpreter as a Reference Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2011-11-21 10:03 -0800
      Re: Using the Python Interpreter as a Reference Travis Parks <jehugaleahsa@gmail.com> - 2011-11-21 16:07 -0800
  Re: Using the Python Interpreter as a Reference Alan Meyer <ameyer2@yahoo.com> - 2011-11-22 13:37 -0500
    Re: Using the Python Interpreter as a Reference Travis Parks <jehugaleahsa@gmail.com> - 2011-11-25 02:55 -0800
      Re: Using the Python Interpreter as a Reference Chris Angelico <rosuav@gmail.com> - 2011-11-25 22:10 +1100
  Re: Using the Python Interpreter as a Reference rusi <rustompmody@gmail.com> - 2011-11-25 09:11 -0800
    RE: Using the Python Interpreter as a Reference "Sells, Fred" <fred.sells@adventistcare.org> - 2011-11-25 23:22 -0500
    Re: Using the Python Interpreter as a Reference Matt Joiner <anacrolix@gmail.com> - 2011-11-26 23:19 +1100
  Re: Using the Python Interpreter as a Reference Alec Taylor <alec.taylor6@gmail.com> - 2011-11-27 05:46 +1100
  Re: Using the Python Interpreter as a Reference Rick Johnson <rantingrickjohnson@gmail.com> - 2011-11-26 10:53 -0800
    Re: Using the Python Interpreter as a Reference Chris Angelico <rosuav@gmail.com> - 2011-11-27 06:34 +1100
      Re: Using the Python Interpreter as a Reference Rick Johnson <rantingrickjohnson@gmail.com> - 2011-11-26 13:15 -0800
    Re: Using the Python Interpreter as a Reference Travis Parks <jehugaleahsa@gmail.com> - 2011-11-27 14:21 -0800
      Re: Using the Python Interpreter as a Reference Colin Higwell <colinh@somewhere.invalid> - 2011-11-27 23:02 +0000
      Re: Using the Python Interpreter as a Reference Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-27 23:55 +0000
        Re: Using the Python Interpreter as a Reference Chris Angelico <rosuav@gmail.com> - 2011-11-28 11:26 +1100
        Re: Using the Python Interpreter as a Reference Travis Parks <jehugaleahsa@gmail.com> - 2011-11-28 10:03 -0800
        Re: Using the Python Interpreter as a Reference Ian Kelly <ian.g.kelly@gmail.com> - 2011-11-28 12:32 -0700
          Re: Using the Python Interpreter as a Reference Neil Cerutti <neilc@norwich.edu> - 2011-11-28 20:20 +0000
            Re: Using the Python Interpreter as a Reference Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2011-11-29 09:48 +1300
              Re: Using the Python Interpreter as a Reference Neil Cerutti <neilc@norwich.edu> - 2011-11-28 21:11 +0000
          Re: Using the Python Interpreter as a Reference Travis Parks <jehugaleahsa@gmail.com> - 2011-11-28 13:34 -0800
          Re: Using the Python Interpreter as a Reference Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-28 22:24 +0000
            Re: Using the Python Interpreter as a Reference Chris Angelico <rosuav@gmail.com> - 2011-11-29 09:48 +1100
            Re: Using the Python Interpreter as a Reference Travis Parks <jehugaleahsa@gmail.com> - 2011-11-28 18:42 -0800
              Re: Using the Python Interpreter as a Reference Chris Angelico <rosuav@gmail.com> - 2011-11-29 13:57 +1100
                Re: Using the Python Interpreter as a Reference Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-29 08:12 +0000
                Re: Using the Python Interpreter as a Reference Dave Angel <d@davea.name> - 2011-11-29 03:53 -0500
              Re: Using the Python Interpreter as a Reference Ian Kelly <ian.g.kelly@gmail.com> - 2011-11-28 21:56 -0700
        Re: Using the Python Interpreter as a Reference DevPlayer <devplayer@gmail.com> - 2011-11-28 16:54 -0800
          Re: Using the Python Interpreter as a Reference DevPlayer <devplayer@gmail.com> - 2011-11-28 16:59 -0800
          Re: Using the Python Interpreter as a Reference Chris Angelico <rosuav@gmail.com> - 2011-11-29 12:49 +1100
            Re: Using the Python Interpreter as a Reference Travis Parks <jehugaleahsa@gmail.com> - 2011-11-28 19:00 -0800
            Re: Using the Python Interpreter as a Reference Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-29 08:04 +0000
              Re: Using the Python Interpreter as a Reference DevPlayer <devplayer@gmail.com> - 2011-12-01 10:03 -0800
                Re: Using the Python Interpreter as a Reference Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-12-02 00:43 +0000
                Re: Using the Python Interpreter as a Reference Chris Angelico <rosuav@gmail.com> - 2011-12-02 13:02 +1100
                RE: Using the Python Interpreter as a Reference "Sells, Fred" <fred.sells@adventistcare.org> - 2011-12-02 15:29 -0500
                Re: Using the Python Interpreter as a Reference Devin Jeanpierre <jeanpierreda@gmail.com> - 2011-12-02 15:58 -0500
      Re: Using the Python Interpreter as a Reference Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2011-11-29 09:40 +1300
        Re: Using the Python Interpreter as a Reference Travis Parks <jehugaleahsa@gmail.com> - 2011-11-28 13:29 -0800
          Re: Using the Python Interpreter as a Reference Chris Angelico <rosuav@gmail.com> - 2011-11-29 08:57 +1100
          Re: Using the Python Interpreter as a Reference Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-28 22:57 +0000
            Re: Using the Python Interpreter as a Reference Travis Parks <jehugaleahsa@gmail.com> - 2011-11-28 18:57 -0800

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