Rob Cliffe writes:
Perhaps where you're not laying out a table,
I'm an economist Oh goody! *Please* tell me what our Government needs to do to grow the UK economy and curb inflation. I'll inform my MP immediately. 😁 Seriously though ... , laying out tables is what I do. :-) Getting serious:
but constructing a human-readable string? So s1 + ' ' + s2 + ' ' + s3 or ' '.join((s1, s3, s3)) would become s1 & s2 & s3 saving you a bit of typing. Just sayin'.
str '+' has long been quite rare in my coding. str concatenation is almost never in an inner loop, or slighly more complex formatting is the point. f-strings and .format save you the type conversion to str. So I don't find that occasional saving at all interesting. A vanishingly small number of my str constructions involve only strs with trivial formatting.
What interests me about the proposal is the space-collapsing part, which a naive f-string would do incorrectly if, say, s2 == '' or s3 == '\t\t\ttabs to the left of me'. But where does this space-surrounded str data come from? I would say: Very often in real-life cases it doesn't. So using '&' would be equivalent to stripping the strings and applying ' '.join(). And more concise, and IMHO more readable (albeit, as Mr Berlier helpfully informs us, less efficient 😁). But I can imagine cases where the leftmost string starts with indentation to start a paragraph (or to correctly indent Python code), which you want to preserve. Or perhaps even to make it start in the correct column of a table, ha-ha. As for trailing whitespace in the rightmost string ... Hm, I can't think of a use case ATM. I just thought it would be nice to make the operation symmetrical. s1 & s2 *could* be defined as equivalent to (s1.rstrip() + ' ' + s2.lstrip()).rstrip() (and it would still be associative). Would this be practicality beating
On 07/03/2023 07:26, Stephen J. Turnbull wrote: purity, or a hideous symmetry breaking? I didn't highlight it before, so let me take the opportunity now: One of the examples I listed shows another use case: constructing an operating system command and ensuring that the parameters are separated by (at least) one space. Bear with me while I repeat it: Lib\site-packages\numpy\distutils\system_info.py:2677: cmd = config_exe + ' ' + self.append_config_exe + ' ' + option cmd = config_exe & self.append_config_exe & option Best wishes Rob Cliffe
Steve