list of polynomial functions

[Fredrik Lundh]

Tim Chase wrote:

>> The `i` is the problem.  It's not evaluated when the lambda
>> *definition* is executed but when the lambda function is
>> called.  And then `i` is always == `n`.  You have to
>> explicitly bind it as default value in the lambda definition:
>>
>>  	polys.append(lambda x, i=i: polys[i](x)*x)
>>
>> Then it works.
> 
> Just to sate my curiosity, why can the lambda find "polys", but 
> not find "i"?  If what you're describing is the case, then it 
> seems to me that the following code should work too:

it's not that it cannot find it, it's that if you use a closure, i will 
have the same value for all lambdas.

> There's some subtle behavior here that I'm missing.

lexical closures bind to names, default arguments bind to values.

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