Re: Program calling unwanted functions

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Date	Mon, 22 Dec 2014 16:48:44 -0700
Subject	Re: Program calling unwanted functions
From	Ian Kelly <ian.g.kelly@gmail.com>
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On Dec 22, 2014 2:37 PM, "Dave Angel" <davea@davea.name> wrote:
>
> I'll pick on one function first, called instructions().  If the user
types something invalid, you print "Invalid input." and call the function
again.  In this case, because the call is at the end, no harm is usually
done, but it would be tricky to explain why.  If the user happened to type
the wrong input 1000 times, you'd hit a recursion limit and crash, but
that's unlikely unless you have a very stubborn user.

Point of interest, Python (or at least CPython) doesn't optimize tail-call
recursion, so in fact this sort of unbounded recursion (a "stack leak", if
you will) is equally bad no matter where it appears in the function.

Thread

Program calling unwanted functions Luke Tomaneng <luketomaneng@gmail.com> - 2014-12-22 11:55 -0800
  Re: Program calling unwanted functions John Gordon <gordon@panix.com> - 2014-12-22 20:09 +0000
  Re: Program calling unwanted functions Dave Angel <davea@davea.name> - 2014-12-22 15:35 -0500
  Re: Program calling unwanted functions Ian Kelly <ian.g.kelly@gmail.com> - 2014-12-22 16:48 -0700
  Re: Program calling unwanted functions Dave Angel <davea@davea.name> - 2014-12-22 18:57 -0500
    Re: Program calling unwanted functions sohcahtoa82@gmail.com - 2014-12-22 16:04 -0800
      Re: Program calling unwanted functions Ian Kelly <ian.g.kelly@gmail.com> - 2014-12-22 17:12 -0700
      Re: Program calling unwanted functions Dave Angel <davea@davea.name> - 2014-12-22 19:12 -0500

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