Le lundi 10 août 2015, Eric V. Smith <eric@trueblade.com> a écrit :
On 08/10/2015 10:18 AM, Victor Stinner wrote:
> Hi,
> I read the PEP but I don't understand how it is implemented. For me, it
> should be a simple preprocessor:
> - f'x={x}' is replaced with 'x={0}'.format(x) by the compiler
> - f'x={1+1}' is replaced with 'x={0}'.format(1+1)
> - f'x={foo()!r}' is replaced with 'x={0!r}'.format(foo())
> - ...
> That's all. No new language, no new function or method.

There is no new function or method being proposed. The "pre-processor"
is being implemented as the ast is being built. As the PEP says, though,
the expressions supported aren't exactly the same, so a simple
conversion to str.format syntax isn't possible.

Can you please provide example(s) of f-string(s) which cannot be replaced by a call to .format() like I did?