Hi.

funcs = [ lambda x: x**i for i in range( 5 ) ]
print funcs[0]( 2 )

This gives me
16

When I was excepting
1

Does anyone know why?

Just the way Python lambda expressions bind their variable references. Inner 'i' references the outer scope's 'i' variable and not its value 'at the time the lambda got defined'.


And more importantly, what's the simplest way to achieve the latter? :)

Try giving the lambda a default parameter (they get calculated and have their value stored at the time the lambda is defined) like this:
  funcs = [ lambda x, i=i: x**i for i in range( 5 ) ]


  Hope this helps.

  Best regards,
    Jurko Gospodnetić

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