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Fear and suspicion of lambdas, was Re: Meta decorator with parameters, defined in explicit functions

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Lawrence D’Oliveiro wrote:

> On Tuesday, June 28, 2016 at 5:03:08 PM UTC+12, Ben Finney wrote:
> 
>> I would like to see a more Pythonic, more explicit and expressive
>> replacement with its component parts easily understood.
> 
> I don’t know why this fear and suspicion of lambdas is so widespread among
> Python users ... former Java/C# programmers, perhaps?

If there is "fear" I don't share it. However, for

foo = lambda <args>: <expr>

there is syntactic sugar in Python that allows you to write it as

def foo(<args>):
    return <expr>

with the nice side effects that it improves the readability of tracebacks 
and allows you to provide a docstring.

So yes, assigning a lambda to a name raises my "suspicion".

If a lambda is provided as an argument or as part of an expression I wonder 
how it is tested, and if even if it is trivial like

def reduce(items, func=lambda x, y: x + y): ...

the alternative

def reduce(items, func=add): ...

looks more readable in my eyes even though somewhere -- under the rug or in 
the operator module -- you need

def add(x, y):
   """
   >>> add(3, 4)
   7
   """
   return x + y

>>     decorator_with_args = lambda decorator: lambda *args, **kwargs: 
lambda func: decorator(func, *args, **kwargs)
> 
> Ah, I see why there are 3 lambdas, instead of 2. It’s so that you can 
write

I have a suspicion that there would not have been a correction "I see why 
there are three functions instead of two" ;)

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Meta decorator with parameters, defined in explicit functions Ben Finney <ben+python@benfinney.id.au> - 2016-06-28 15:02 +1000
  Re: Meta decorator with parameters, defined in explicit functions Paul Rubin <no.email@nospam.invalid> - 2016-06-27 23:08 -0700
  Re: Meta decorator with parameters, defined in explicit functions Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2016-06-28 18:39 +1000
  Re: Meta decorator with parameters, defined in explicit functions Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-06-29 19:43 -0700
    Re: Meta decorator with parameters, defined in explicit functions Steven D'Aprano <steve@pearwood.info> - 2016-06-30 13:49 +1000
    Fear and suspicion of lambdas, was Re: Meta decorator with parameters, defined in explicit functions Peter Otten <__peter__@web.de> - 2016-06-30 09:25 +0200
      Re: Fear and suspicion of lambdas, was Re: Meta decorator with parameters, defined in explicit functions Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-06-30 00:43 -0700
        Re: Fear and suspicion of lambdas, was Re: Meta decorator with parameters, defined in explicit functions Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2016-06-30 18:00 +1000
        Re: Fear and suspicion of lambdas, was Re: Meta decorator with parameters, defined in explicit functions Peter Otten <__peter__@web.de> - 2016-06-30 10:41 +0200
    Re: Fear and suspicion of lambdas, was Re: Meta decorator with parameters, defined in explicit functions dieter <dieter@handshake.de> - 2016-07-01 09:04 +0200
      Re: Fear and suspicion of lambdas, was Re: Meta decorator with parameters, defined in explicit functions Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-01 21:25 +0100
        Re: Fear and suspicion of lambdas, was Re: Meta decorator with parameters, defined in explicit functions Ben Finney <ben+python@benfinney.id.au> - 2016-07-02 11:52 +1000
        Re: Fear and suspicion of lambdas, was Re: Meta decorator with parameters, defined in explicit functions dieter <dieter@handshake.de> - 2016-07-02 08:57 +0200
        Re: Fear and suspicion of lambdas, was Re: Meta decorator with parameters, defined in explicit functions Ben Finney <ben+python@benfinney.id.au> - 2016-07-02 18:00 +1000
  Re: Meta decorator with parameters, defined in explicit functions Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-06-29 19:50 -0700
  Re: Meta decorator with parameters, defined in explicit functions Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-07-01 15:08 -0700
    Re: Meta decorator with parameters, defined in explicit functions Ian Kelly <ian.g.kelly@gmail.com> - 2016-07-01 23:09 -0600
      Re: Meta decorator with parameters, defined in explicit functions Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-07-01 23:40 -0700
        Re: Meta decorator with parameters, defined in explicit functions Ian Kelly <ian.g.kelly@gmail.com> - 2016-07-02 22:48 -0600
          Re: Meta decorator with parameters, defined in explicit functions Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-07-02 22:37 -0700
            Re: Meta decorator with parameters, defined in explicit functions Ian Kelly <ian.g.kelly@gmail.com> - 2016-07-03 05:52 -0600
              Re: Meta decorator with parameters, defined in explicit functions Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-07-03 14:17 -0700
                Re: Meta decorator with parameters, defined in explicit functions Ian Kelly <ian.g.kelly@gmail.com> - 2016-07-03 16:38 -0600
                Re: Meta decorator with parameters, defined in explicit functions Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-07-03 16:25 -0700
                Re: Meta decorator with parameters, defined in explicit functions Chris Angelico <rosuav@gmail.com> - 2016-07-04 09:39 +1000
                Re: Meta decorator with parameters, defined in explicit functions Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-07-03 16:59 -0700
                Re: Meta decorator with parameters, defined in explicit functions Chris Angelico <rosuav@gmail.com> - 2016-07-04 10:06 +1000
                Re: Meta decorator with parameters, defined in explicit functions Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-07-03 17:23 -0700
                Re: Meta decorator with parameters, defined in explicit functions Ian Kelly <ian.g.kelly@gmail.com> - 2016-07-03 18:01 -0600
                Re: Meta decorator with parameters, defined in explicit functions Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-07-03 17:06 -0700
                Re: Meta decorator with parameters, defined in explicit functions Ian Kelly <ian.g.kelly@gmail.com> - 2016-07-03 18:20 -0600
    Re: Meta decorator with parameters, defined in explicit functions Ben Finney <ben+python@benfinney.id.au> - 2016-07-02 15:32 +1000
    Re: Meta decorator with parameters, defined in explicit functions Ian Kelly <ian.g.kelly@gmail.com> - 2016-07-01 23:53 -0600

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