diff options
| -rw-r--r-- | Doc/whatsnew/3.10.rst | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/Doc/whatsnew/3.10.rst b/Doc/whatsnew/3.10.rst index 7a2f4f8c82f..d822dda09d2 100644 --- a/Doc/whatsnew/3.10.rst +++ b/Doc/whatsnew/3.10.rst @@ -166,6 +166,48 @@ See :class:`typing.Callable`, :class:`typing.ParamSpec`, (Contributed by Ken Jin in :issue:`41559`.) +Better error messages in the parser +----------------------------------- + +When parsing code that contains unclosed parentheses or brackets the interpreter +now includes the location of the unclosed bracket of parentheses instead of displaying +*SyntaxError: unexpected EOF while parsing* or pointing to some incorrect location. +For instance, consider the following code (notice the unclosed '{'): + +.. code-block:: python + + expected = {9: 1, 18: 2, 19: 2, 27: 3, 28: 3, 29: 3, 36: 4, 37: 4, + 38: 4, 39: 4, 45: 5, 46: 5, 47: 5, 48: 5, 49: 5, 54: 6, + some_other_code = foo() + +previous versions of the interpreter reported confusing places as the location of +the syntax error: + +.. code-block:: text + + File "example.py", line 3 + some_other_code = foo() + ^ + SyntaxError: invalid syntax + +but in Python3.10 a more informative error is emitted: + +.. code-block:: text + + File "example.py", line 1 + expected = {9: 1, 18: 2, 19: 2, 27: 3, 28: 3, 29: 3, 36: 4, 37: 4, + ^ + SyntaxError: '{' was never closed + + +In a similar way, errors involving unclosed string literals (single and triple +quoted) now point to the start of the string instead of reporting EOF/EOL. + +These improvements are inspired by previous work in the PyPy interpreter. + +(Contributed by Pablo Galindo in :issue:`42864` and Batuhan Taskaya in +:issue:`40176`.) + Other Language Changes ====================== |