Antoon Pardon writes: > Op 02-10-16 om 07:59 schreef Rustom Mody: >> >> You are explaining the mechanism behind the bug. Thanks. The bug >> remains. My new car goes in reverse when I put it in first gear but >> only on full-moon nights with the tank on reserve when the left light >> is blinking The engineer explains the interesting software bug in the >> new PCB. Interesting. But the bug remains >> >> Likewise here: >> >> [2 ** i for i in[1,2]] == [2**1, 2**2] >> >> yet this fails >> >> [lambda x: x + i for i in [1,2]] == [lambda x:x+1, lambda x:x=2] >> >> is a bug for anyone including the OP of this thread
(That x=2 should be x+2.) (And that == for functions needs to be understood mathematically. In Python, even (lambda : 1) == (lambda : 1) may (must?) be False.) > I once suggested that a list comprehension like [<exp> for i in > <iterator>] should be implemented as [(lambda i:<exp>)(i) for i in > <iterator>]. > > As far a I can see, it would behave as expected in all cases. It's strictly circular as-is (the latter is an instance of the former), and it needs spelled-out a bit in order to cover comprehensions of multiple variables. I like it anyway. On the other hand, fortunately, it's simple to *do* this in practice when the need arises, without waiting for anyone to change the language. (So is the default-parameter trick.) -- https://mail.python.org/mailman/listinfo/python-list
