PEP 786: Precision and Modulo-Precision Flag format specifiers for integer fields

[jb2170]

New rebased PR with the correct branch name to avoid confusion (786 not 791).

Thank you Alyssa for sponsoring this!

Relevant discussions, issues, PRs linked

• https://discuss.python.org/t/implement-precision-format-spec-for-int-type-data/80760
• https://github.com/python/cpython/pull/131926
• https://github.com/python/cpython/issues/74756
• https://github.com/python/peps/pull/4365

Basic requirements (all PEP Types)

• [x] Read and followed PEP 1 & PEP 12
• [x] File created from the latest PEP template
• [x] PEP has next available number, & set in filename (pep-NNNN.rst), PR title (PEP 123: <Title of PEP>) and PEP header
• [x] Title clearly, accurately and concisely describes the content in 79 characters or less
• [x] Core dev/PEP editor listed as Author or Sponsor, and formally confirmed their approval: @ncoghlan
• [x] Author, Status (Draft), Type and Created headers filled out correctly
• [ ] PEP-Delegate, Topic, Requires and Replaces headers completed if appropriate: Is a PEP-Delegate required?
• [x] Required sections included
  • [x] Abstract (first section)
  • [x] Copyright (last section; exact wording from template required)
• [x] Code is well-formatted (PEP 7/PEP 8) and is in code blocks, with the right lexer names if non-Python: everything but 80-column line length, so as to avoid tedious re-aligning during this draft stage
• [x] PEP builds with no warnings, pre-commit checks pass and content displays as intended in the rendered HTML
• [x] Authors/sponsor added to .github/CODEOWNERS for the PEP

Standards Track requirements

• [x] PEP topic discussed in a suitable venue with general agreement that a PEP is appropriate
• [ ] Suggested sections included (unless not applicable)
  • [x] Motivation: included in Rationale
  • [x] Rationale
  • [x] Specification: Abstract is RFC 2119 style
  • [x] Backwards Compatibility
  • [x] Security Implications: not needed?
  • [x] How to Teach This: Examples And Teaching section
  • [ ] Reference Implementation
  • [x] Rejected Ideas
  • [x] Open Issues: None so far
• [x] Python-Version set to valid (pre-beta) future Python version, if relevant
• [x] Any project stated in the PEP as supporting/endorsing/benefiting from the PEP formally confirmed such: none
• [x] Right before or after initial merging, PEP discussion thread created and linked to in Discussions-To and Post-History

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📚 Documentation preview 📚: https://pep-previews--4416.org.readthedocs.build/pep-0786/