[issue20496] function definition tutorial encourages bad practice
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New submission from Alan Isaac: Section 4.6 of the tutorial introduces function definition: http://docs.python.org/3/tutorial/controlflow.html#defining-functions The first example defines a function that *prints* a Fibonacci series. A basic mistake made by students new to programming is to use a function to print values rather than to return them. In this sense, the example encourages bad practice and misses an opportunity to instruct. Since they have already met lists in Section 3, I suggest that returning a list of the values and then printing the list would enhance the tutorial. ---------- assignee: docs@python components: Documentation messages: 210077 nosy: aisaac, docs@python priority: normal severity: normal status: open title: function definition tutorial encourages bad practice type: enhancement _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue20496> _______________________________________
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Terry J. Reedy added the comment: There is a later example introduced by "It is simple to write a function that returns a list of the numbers of the Fibonacci series, instead of printing it:" that does exactly what you suggest. ---------- nosy: +terry.reedy _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue20496> _______________________________________
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Berker Peksag added the comment: I agree with Terry. The print example is also useful to show the implicit return value of fib(). Quoting from the same section: [...] In fact, even functions without a return statement do return a value, albeit a rather boring one. This value is called None [...] ---------- nosy: +berker.peksag resolution: -> not a bug stage: -> resolved status: open -> closed _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue20496> _______________________________________
participants (3)
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Alan Isaac
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Berker Peksag
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Terry J. Reedy