Documentation
On this page: https://docs.python.org/3.14/library/string.html#grammar-token-format-spec-format_spec
format_spec: [options][width_and_precision][type]
options: [[fill]align][sign]["z"]["#"]["0"]
fill: <any character>
align: "<" | ">" | "=" | "^"
sign: "+" | "-" | " "
width_and_precision: [width_with_grouping][precision_with_grouping]
width_with_grouping: [width][grouping]
precision_with_grouping: "." [precision][grouping]
width: digit+
precision: digit+
grouping: "," | "_"
type: "b" | "c" | "d" | "e" | "E" | "f" | "F" | "g"
| "G" | "n" | "o" | "s" | "x" | "X" | "%"The precision_with_grouping syntaxe is wrong, because it accepts . without precision or grouping. But
>>> f'{1234.1234:.f}'
Traceback (most recent call last):
File "<python-input-17>", line 1, in <module>
f'{1234.1234:.f}'
^^^^^^^^^^^^^^
ValueError: Format specifier missing precision(The error does not mention grouping either)
The right syntax should be
precision_with_grouping: "." precision [grouping] | "." grouping
Linked PRs
Documentation
On this page: https://docs.python.org/3.14/library/string.html#grammar-token-format-spec-format_spec
The
precision_with_groupingsyntaxe is wrong, because it accepts.withoutprecisionorgrouping. But(The error does not mention grouping either)
The right syntax should be
Linked PRs
precision_with_groupingin format description #134608precision_with_groupingin format description (GH-134608) #135015