Calling a generator multiple times

Alex Martelli aleaxit at yahoo.com
Sun Dec 9 00:14:00 CET 2001


Bruce Eckel wrote:
        ...
> I believe that this is too restrictive a definition. My experience
> of generators (from C++/STL) is that a generator is simply a
> callable entity that returns an object every time you call it; this
> call takes no arguments so it is "generating" objects rather than

...so a Python generator such as:

def imageneratorhonest(sequence1, sequence2):
    for item in sequence1: yield item
    for item in sequence2: yield item

isn't a generator...?  Unfortunately, clashes with some preexisting 
definition are inevitable each time a common term is adopted in a 
specifical technical sense in any universe of discourse -- package, module, 
function, type, method, class, instance, exception, attribute, item, just 
to give a few examples, are all terms which may be usefully used in some 
sense or other, but since Python has adopted each of them in one specific 
sense (sometimes the same as a few other languages, sometimes not), it's 
best to avoid using them in their other senses when talking about Python.

I learned this the hard way when writing about bridge: perfectly reasonable 
idioms such as "on the other hand", "the trick is", "a good deal", etc, 
cause far too much confusion when used in a universe of language where 
"hand", "trick" and "deal" acquire specific, specialized meanings:-).


Alex




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