[Python-ideas] pep-0484 - Forward references and Didactics - be orthogonal

[Prof. Dr. L. Humbert]

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On 28.08.2015 15:58, Petr Viktorin wrote:
…
>> It is indeed possible to run the following code
>> /
>> from typing import List
>> class Tree:
>>      def __init__(self, left: 'Tree', right: 'Tree'):
>>          self.left = left
>>          self.right = right
>>      def leaves(self) -> List['Tree']:
>>          return []
>> def greeting(name: 'str') -> 'str':
>>      return 'Hello ' + name
>> \
>>
…
pv> You can put the entire hint in a string:
pv> def leaves(self) -> 'List[Tree]':

TNX … solves the problem in this example and makes it
orthogonal.

Next showstopper will come, when working on/with datastructures, which
contains entangled class-structures, perhaps the instantiation of a
class, when we have to use

	self.node = Node(…)
but not
	self.node= 'Node'(…)

So I think, we as educators have to live with this pedagogical
»suboptimal« solution(s) and have to communicate those non-orthogonal
notation and make clear, what the reason is all about.

	TNX
	Ludger

- -- 
https://twitter.com/n770
http://ddi.uni-wuppertal.de/
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