Chris Angelico writes: > I have to defer to someone who knows in more detail here, but the > parser will look ahead one "token", whatever a token is. (Technically > it doesn't backtrack, it looks ahead - same difference.)
Tokens are basically keywords, identifiers, most single punctuation characters, and indentation. Some strings of punctuation are tokens by special dispensation. > In order for the ternary-if to work, the expression before the if > has to be of a more restricted type than just "any expression" (for > instance, you can't put a lambda function there, unless you > parenthesize it). It's not that it's a restricted expression, it's that a valid lambda will consist of a syntactically complete expression. If you then place "if" after that lambda without parenthesizing, the parser will think that the lambda contains the whole ternary expression because pretty much any Python expression has a value that can be implicitly cast to bool. Steve _______________________________________________ Python-ideas mailing list Python-ideas@python.org https://mail.python.org/mailman/listinfo/python-ideas Code of Conduct: http://python.org/psf/codeofconduct/
