fun with lambdas

bonono at gmail.com bonono at gmail.com
Fri Oct 21 05:33:02 CEST 2005



You are asking it to return a list of lambda, not its evaluated value.

map(lambda x: f(x,0), [0,1,2]) works.

[ f(o) for o in [0,1,2] ] works too.

Juan Pablo Romero wrote:
> Hello!
>
> given the definition
>
> def f(a,b): return a+b
>
> With this code:
>
> fs = [ lambda x: f(x,o) for o in [0,1,2]]
>
> or this
>
> fs = []
> for o in [0,1,2]:
>     fs.append( lambda x: f(x,o) )
>
> I'd expect that fs contains partial evaluated functions, i.e.
>
> fs[0](0) == 0
> fs[1](0) == 1
> fs[2](0) == 2
>
> But this is not the case :(
>
> What is happening here?
>
>
> Nevertheless, this code does work
>
> fs = [ eval("lambda x: f(x,%d)" % o) for o in [0,1,2,3]]
> 
> Thanks.
> 
>    Juan Pablo




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