bpo-35169: Improve error messages for forbidden assignments. #10342
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| static int | ||
| is_forbidden_name(const char *name) |
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Can we not duplicate this by having ast_for_call turn the name into an identifier and passing it to forbidden_name?
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I tried this initially. But this needed to add more complex code at calling places if we want to raise the same error "expression cannot contain assignment" for both f(0 = a) and f(False = a).
But if "cannot assign to False" is good enough or even better for the latter case, the code can be simplified.
| ast_error(c, chch, | ||
| "keyword can't be an expression"); | ||
| "expression cannot contain assignment, " | ||
| "perhaps you meant \"==\"?"); |
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As a matter of style, I don't think we should use the second person ("you") in error messages.
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I agree. Could you please suggest better error message?
I based this error message on the error messages for Python 2 style print. There are also other error messages that contain "you":
"Missing parentheses in call to 'print'. Did you mean print(%U%s)?""unsupported operand type(s) for %.100s: '%.100s' and '%.100s'. Did you mean \"print(<message>, file=<output_stream>)\"?""if you give only one argument to maketrans it must be a dict""new-line character seen in unquoted field - do you need to open the file in universal-newline mode?""iterator should return strings, not %.200s (did you open the file in text mode?)""utime: you may specify either 'times' or 'ns' but not both""Binding %d has no name, but you supplied a dictionary (which has only names)."
Perhaps we should make them less personalized too. But this is other issue.
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https://bugs.python.org/issue35169