Commit Graph

9 Commits

Author SHA1 Message Date
Jim Mussared af162257d3 docs/library/builtins.rst: Add module title.
This fixes the rendering on library/index.rst.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-08-17 11:26:24 +10:00
Damien George 3c4bfd1dec py/objexcept: Support errno attribute on OSError exceptions.
This commit adds the errno attribute to exceptions, so code can retrieve
errno codes from an OSError using exc.errno.

The implementation here simply lets `errno` (and the existing `value`)
attributes work on any exception instance (they both alias args[0]).  This
is for efficiency and to keep code size down.  The pros and cons of this
are:

Pros:
- more compatible with CPython, less difference to document and learn
- OSError().errno will correctly return None, whereas the current way of
  doing it via OSError().args[0] will raise an IndexError
- it reduces code size on most bare-metal ports (because they already have
  the errno qstr)
- for Python code that uses exc.errno the generated bytecode is 2 bytes
  smaller and more efficient to execute (compared with exc.args[0]); so
  bytecode loaded to RAM saves 2 bytes RAM for each use of this attribute,
  and bytecode that is frozen saves 2 bytes flash/ROM for each use
- it's easier/shorter to type, and saves 2 bytes of space in .py files that
  use it (for each use)

Cons:
- increases code size by 4-8 bytes on minimal ports that don't already have
  the `errno` qstr
- all exceptions now have .errno and .value attributes (a cpydiff test is
  added to address this)

See also #2407.

Signed-off-by: Damien George <damien@micropython.org>
2021-04-23 22:03:46 +10:00
Paul Sokolovsky 465d84b7e7 docs/library: Add CPython docs xref to each pertinent module.
Cross-reference text/link is implemented as RST substitution, so easy to
consistently.
2017-07-02 15:37:31 +03:00
Paul Sokolovsky d42bb58c33 docs/builtins: Add AssertionError, SyntaxError, ZeroDivisionError.
Also, update heading of 1st sections to "Functions and types".
2017-07-01 22:20:49 +03:00
Paul Sokolovsky bc790b5145 docs/builtins: List builtin exceptions.
If for nothing else, then at least to cross-reference them.
2017-06-24 23:45:38 +03:00
Paul Sokolovsky bcf3c8bf17 docs/library/builtins: int: Add notice on byteorder param for to/from_bytes. 2017-04-09 00:06:54 +03:00
Damien George f1b2b1b600 docs/library/builtins: Add docs for delattr and slice. 2016-10-25 11:02:47 +11:00
Mike Causer ce166e6b68 docs: Spelling mistakes 2016-08-02 11:17:46 +03:00
Paul Sokolovsky 0cec4e9bb8 docs/builtins: Enumerate all builtin functions implemented.
Based on unix version. No descriptions so far.
2016-06-09 00:24:52 +03:00