String reboot - (1a) incidental whitespace
guy.steele at oracle.com
Mon Apr 22 19:16:56 UTC 2019
I think we actually are in “violent agreement” here, Alex, but just to be sure, see comments below.
> On Apr 22, 2019, at 3:04 PM, Alex Buckley <alex.buckley at oracle.com> wrote:
> Nope, I don't think multi-line string literals are an attractive nuisance in any way. We should NOT deem it incorrect to refactor a sequence of concatenations into a single multi-line string literal.
I didn’t say (or mean to imply that). I think it’s a great thing to refactor concatenations into a single multi-line string literal WHEN IT IS DONE CORRECTLY.
However, if you blindly pull out the concatenations and thereby introduce newlines into the string when they were not there before and doing so violates some contract downstream, THAT IS AN INCORRECT TRANSFORMATION.
We certainly agree that it would be a good thing if everything that might be downstream were in fact reasonably tolerant of newlines.
BUT IF YOU DON’T KNOW FOR SURE THAT WHAT IS DOWNSTREAM IS TOLERANT OF NEWLINES, AND YOU BLINDLY TRANSFORM A STRING CONCATENATION INTO A MULTI-LINE STRING LITERAL THAT INCLUDES NEWLINES WHERE THERE WERE NONE BEFORE, THAT IS A BAD THING.
And a feature that makes it too easy to accidentally do a bad thing _might_ be considered an attractive nuisance, AS OPPOSED TO MY SCREAMING ALL-CAPS, WHICH ARE A REPULSIVE NUISANCE.
> Developers are chomping at the bit to do it, and if we cast doubt on the ability then we're wasting everyone's time. We should deem it correct, and 99% of the time no-one will care that newline characters exist in the string. The rare library that subtly misbehaves or (and this is the better option) actually blow ups when seeing newlines will feel great pressure to become more liberal in what it accepts, and that is a good thing.
And it would probably also be a good thing to have a way to say that a newline in the string literal should not be part of the string content. C programmers are certainly quite used to sticking a backslash in front of a newline to mean “not really a newline here”.
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