Dave Angel wrote: [Fixed quotation]
> On 03/26/2015 01:09 AM, Ian Kelly wrote: >>>>> Thomas 'PointedEars' Lahn wrote: >>>>>> <https://docs.python.org/3/reference/lexical_analysis.html#string->>>>>> >>>>>> literal-concatenation> >> >> What the grammar that you quoted from shows is that STRING+ is an >> expression. The individual STRINGs of a STRING+ are not expressions, >> except to the extent that they can be parsed in isolation as a >> STRING+. By the same token, a STRING+ is a single string literal, not >> an aggregate of several. > > That's the way I also read the BNF. Then I am afraid you need to refresh your knowledge of formal grammars. > But something I cannot find in that chapter of the reference is the > definition of STRING+ You *definitely* need to refresh your knowledge of formal grammars. “STRING+” in this flavor of _E_BNF is – rather obviously – equivalent to <multiple-string> ::= <STRING> <STRING>* <STRING> ::= '"' <no-unescaped-doublequote>* '"' | "'" <no-unescaped-singlequote>* "'" | '"""' <no-triple-doublequote>* '"""' | "'''" <no-triple-singlequote>* "'''" in BNF and multiple-string = STRING *STRING STRING = '"' *no-unescaped-doublequote '"' / "'" *no-unescaped-singlequote '"' / '"""' *no-unescaped-triple-doublequote '"""' / "'''" *no-unescaped-triple-singlequote "'''" in ABNF. I suspect that in this flavor of EBNF the definition of STRING looks similar to the following: STRING: ('"' no_unescaped_doublequote* '"' | "'" no_unescaped_singlequote* "'" | '"""' no_unescaped_triple_doublequote* '"""' | "'''" no_unescaped_triple_singlequote* "'''") Definition of the still undefined goal symbols is left as an exercise to the reader. -- PointedEars Twitter: @PointedEars2 Please do not cc me. / Bitte keine Kopien per E-Mail. -- https://mail.python.org/mailman/listinfo/python-list
