Description
Proposal
Signed negative literals (e.g. -12) currently are represented as an unary negation expression with a positive literal inside. I want to change this to have literals (signed int, unsuffixed int, and floats) to contain a flag that states whether there's a negative sign.
From HIR onwards this is implemented in rust-lang/rust#136860 which shows that while moderately invasive, not as invasive as I feared.
Doing the same in the AST will require more care, as macro_rules macros can detect lit fragments, which today do not include negated literals.
The repeated usage of checking for a negated expression of a literal is imo an anti-pattern that we should avoid by accepting this MCP.
Mentors or Reviewers
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work.
Process
The main points of the Major Change Process are as follows:
- File an issue describing the proposal.
- A compiler team member or contributor who is knowledgeable in the area can second by writing
@rustbot second.- Finding a "second" suffices for internal changes. If however, you are proposing a new public-facing feature, such as a
-C flag, then full team check-off is required. - Compiler team members can initiate a check-off via
@rfcbot fcp mergeon either the MCP or the PR.
- Finding a "second" suffices for internal changes. If however, you are proposing a new public-facing feature, such as a
- Once an MCP is seconded, the Final Comment Period begins. If no objections are raised after 10 days, the MCP is considered approved.
You can read more about Major Change Proposals on forge.
Comments
This issue is not meant to be used for technical discussion. There is a Zulip stream for that. Use this issue to leave procedural comments, such as volunteering to review, indicating that you second the proposal (or third, etc), or raising a concern that you would like to be addressed.