[Python-Dev] PEP 498: Literal String Interpolation is ready for pronouncement (original) (raw)

Eric V. Smith eric at trueblade.com
Sat Sep 5 20:16:29 CEST 2015

On 9/5/2015 1:14 PM, Gustavo Carneiro wrote:

Why not allow string concatenation without plus sign only if/when the implementation becomes optimised to allow compile time concatenation? This makes it crystal clear whether the concatenation is compile time or runtime. If we allow it now, it's hard to tell without looking at the CPython source code...

Although you can make it faster than '+', it's not possible for it to be a compile-time concatenation. The PEP calls out that it's an expression that's evaluated at runtime.

I think having strings concatenated with adjacent f-strings follows the principle of least surprise. I also think it won't get used all that often, just as compile-time string concatenation isn't seen with great frequency.

Eric.

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