On 2019-04-03 03:06, Stephan Hoyer wrote:
On Tue, Apr 2, 2019 at 5:43 PM Eric V. Smith <eric@trueblade.com <mailto:eric@trueblade.com>> wrote:
PS: I really tried to find a way to use := in this example so I could put the assignment inside the 'if' statement, but as I think Tim Peters pointed out, without C's comma operator, you can't.
Conceivably cut_prefix could return None if not found. Then you could write something like:
if (stripped := cut_prefix(line, "INFO>")) is not None: print(f"control line {stripped!r}") else: print(f"data line {line!r}")
You could even drop "is not None" in many circumstances, if you know the cut string will be non-empty. That's actually pretty readable:
if stripped := cut_prefix(line, "INFO>"): print(f"control line {stripped!r}") else: print(f"data line {line!r}")
-1 Sometimes you just want to remove it if present, otherwise leave the string as-is. I wouldn't want to have to write: line = line.lcut("INFO>") or line