02:07 pm, 29 Nov 03
learning
Speaking of types, this poor program isn't gonna work even if they could get the syntax right.
For a beginner, is fixing Period1's type to either float or string a good thing or a bad thing?
(And whoa, people still use floppies?)
I'm very curious about teaching programming languages; I asked
htang (who has studied both CS and teaching extensively) about it and she didn't know if there was any conclusive evidence about what is more "natural". Regarding types, it always seemed to me that teaching C++ was needlessly confusing in that the magical "cout" function didn't care about types while everything else did.
Meena wanted to learn about programming so I tried to start her with Python. The first major point of confusion (aside from the minor confusions that are inevitably overcome with teaching) was the difference between "print x" and simply "x" at the prompt, because both seemed to just output x's value.
For a beginner, is fixing Period1's type to either float or string a good thing or a bad thing?
(And whoa, people still use floppies?)
I'm very curious about teaching programming languages; I asked
htang (who has studied both CS and teaching extensively) about it and she didn't know if there was any conclusive evidence about what is more "natural". Regarding types, it always seemed to me that teaching C++ was needlessly confusing in that the magical "cout" function didn't care about types while everything else did.Meena wanted to learn about programming so I tried to start her with Python. The first major point of confusion (aside from the minor confusions that are inevitably overcome with teaching) was the difference between "print x" and simply "x" at the prompt, because both seemed to just output x's value.
eh?
cout isn't a function... and the complicated stuff doesn't happen until you start using stream formatters... and it does care about types... (i assume that you knew the 3 things i just said), so why would you teach it the way you said it? (or perhaps, who taught it that way?)although going into the multitude of ways that a function can be invoked in c++ is probably not a good starting point now that i think of it... i'd just teach printf until [if] you get to the stream aspects of c++...
--scott
Re: eh?
i guess i think of languages as having two aspects: the magic bits, that are orthogonal to the others, and the bits that are built using magic bits. lisp is an example of a langauge that has very few magic bits. c has many more, but "built-in" stuff like printf (even from the beginning) is understandable as a function much like any other function (maybe the varargs stuff is a leap, but not a big one). i suppose the proper way to teach cout is to say that it's another one of the magic bits and not to worry about it until you understand operator overloading, etc., etc. it just makes me uncomfortable, especially when everything else in the language focuses on types.Re: eh?
i agree with your first 3 sentences...there are tons of magic parts to c++, if you wean someone on c++ (not something i'd recommend), then no matter what you're going to have to dodge parts of it...
but i don't follow what you mean by "everything else ... focuses on types"... c++'s cout isn't any less focused on types than the rest of the language, it's just built so that you don't have to do anything for the built in PoD types... and if you want to print a myPoint to a stream, you have to write your own
operator<<to do so... and obviously cout's design indicates a desire to be more type safe than printf (ieint i; sscanf("%f", &i);...)i've drifted from the teaching aspect of this... and IMO, there's no clean way to teach c++ to someone new to programming... i assume people start with the "print" examples because they're very demonstrative... and this is unavoidable unless you start them in the debugger, and teach them that way (i'd think it'd be easy to grasp the control flow/scoping aspects of a language this way)...
--scott
Re: eh?
std::endl is a overloaded function pointer. That blew my mind.Re: eh?
Oops, I should say the functions endl are primarily used as a function pointer.Re: eh?
yeah, that is pretty magical... having never before really thought how that worked, i had to go look at the source to see how it's implemented...--scott
The first is a design feature of C++ (arguably a poor one), and the second is poor teaching (or possibly a poor student). (The fact that the respondent uses parenthesies as quotes in English is somewhat interesting to me, perhaps both speak a language where quotes are not spelled "".)
As to the cout thing, I think the best solution is to not use it until you're ready to introduce operator overloading... because if you teach it before that, it's part of the magic, and not part of the pattern. At the least, you should say that it doesn't match the rest of what's going on, in some ways. Otherwise, you'll end up with confused students who don't know when to expect pow(2,n) and when to expect pow << 2 << n.