On Mon, 17 Mar 2014 21:22:18 +0200, Marko Rauhamaa wrote:
> Chris Angelico <ros...@gmail.com>:
>
>> On Tue, Mar 18, 2014 at 5:15 AM, Marko Rauhamaa <ma...@pacujo.net>
>> wrote:
>>> Is "-2.0" a literal?
>>>
>>> What's the outcome of
>>>
>>> -2.0.__str__()
>>
>> If you mean (-2.0).__str__(), then it returns '-2.0', but that proves
>> nothing.
>
> The point is, you don't need to "philosophize" about complex literals
> when even negative numbers don't have literals in Python.
But Python *does* have complex (well, imaginary to be precise) literals.
The j suffix to a number makes it complex:
py> type(2j)
<class 'complex'>
Complex numbers with both a real and imaginary component are not treated
as literals:
py> import ast
py> ast.dump(ast.parse("2j"))
'Module(body=[Expr(value=Num(n=2j))])'
py> ast.dump(ast.parse("1+2j"))
'Module(body=[Expr(value=BinOp(left=Num(n=1), op=Add(),
right=Num(n=2j)))])'
and in recent versions, the peephole optimizer optimizes them:
py> from dis import dis
py> dis("1+2j")
1 0 LOAD_CONST 2 ((1+2j))
3 RETURN_VALUE
--
Steven
--
https://mail.python.org/mailman/listinfo/python-list
