On 19/11/2017 05:01, Nick Timkovich wrote:
Python does not use U+2010 HYPHEN for the minus operator, it uses the U+002D (-) HYPHEN-MINUS.
In some monospace fonts, there is a subtle difference between U+002D, U+2013 EN DASH, and U+2014 EM DASH, but it's usually hard to tell them *all* apart.
If you want to make a proposal, I'd suggest that you limit it to allowing the U+2010 HYPHEN to be used for names. U+002D simply cannot be changed because it would break billions of lines of code.
On Sat, Nov 18, 2017 at 10:44 PM, Mikhail V
mailto:mikhailwas@gmail.com> wrote: On Sun, Nov 19, 2017 at 3:42 AM, Nick Coghlan
mailto:ncoghlan@gmail.com> wrote: > For anyone tempted to suggest "What about multiple underscores > indicating continuation of the variable name?", that's still a > compatibility problem due to the unary minus operator: > > >>> my--variable > 2 > >>> my---variable > 0
That seems to be another showcase of misfotune that Python uses hyphen for minus operator. I know it is not language designer's fault, because basic ASCII simply did not not include minus character. But do you realise that the **current** problem you are adressing is that font designers forgot to make the minus character (in monospaced font) distinctive from the hyphen character?
Well, what can I say, I just think it should be a reason to make a collective complain to font providers, but not that you should silently accept this and adopt the language design to someone's sloppy font design.
As an aid for monospace die-hards, to minimise the confusion one could publish a style-guide that recommends to disclose the minus operator (currently hyphen char) in spaces, like a - b, and probably disallow the new proposed hyphen character in the beginning of the identifiers. That would still leave potential for confusion because you cant' force everyone to follow style-guides, but one should struggle to break from this cycle anyway.
> > Would hyphens in variable names improve readability sometimes?
For reading code, indeed, always and very much. Of course not in case I would be forced to use monospaced font with a similar minus and hyphen. But in that case I am already accepting the level of readability of 12th century, so this would not make things much worse, and I would simply put spaces around the minus operator and try to highlight it with some strong color.
How about allowing ¬, (ASCII 172, U+00ac, NOT sign), in variable names as in my¬variable - it has the advantages that: - it is visually distinguishable even in mono-spaced fonts, (personally I use mono-spaced all of the time when programming but I know that I am a dinosaur), - is actually on many keyboards as a single character, (I don't know of any which actually produce different characters for minus on the numeric keypad and hyphen elsewhere), so can be typed as a single key press, - Is generally unused AFAIK other than in papers about logic, - It is currently unused in the Python language. This might upset some who would like use it to replace the unary not operator but I suspect that it would be far fewer people than the potential breakages discussed so far. -- Steve (Gadget) Barnes Any opinions in this message are my personal opinions and do not reflect those of my employer. --- This email has been checked for viruses by AVG. http://www.avg.com