On Tue, Mar 25, 2014 at 1:29 PM, Mark H Harris <harrismh...@gmail.com> wrote: > On 3/25/14 2:24 PM, MRAB wrote: >> It's explained in PEP 3131. >> >> Basically, a name should to start with a letter (this has been extended >> to include Chinese characters, etc) or an underscore. >> >> λ is a classified as Lowercase_Letter. >> >> √ is classified as Math_Symbol. > > Thanks much! I'll note that for improvements. Any unicode symbol (that > is not a number) should be allowed as an identifier.
√ cannot be used in identifiers for the same reasons that + and ~ cannot: identifiers are intended to be alphanumeric. √ is not currently the name of an operator, but who knows what may happen in the future? Python generally follows Annex 31 of the Unicode standard in this regard: http://www.unicode.org/reports/tr31/ -- https://mail.python.org/mailman/listinfo/python-list
