{
  "$type": "site.standard.document",
  "bskyPostRef": {
    "cid": "bafyreigbhsxpy2fr2sbtalgfrsxxybg7hr57f6pkqwf4oelvsqfmols2xm",
    "uri": "at://did:plc:ivbknywyskln22er3nkssdhl/app.bsky.feed.post/3mg55qgilph22"
  },
  "path": "/t/subset-enums/24048#post_4",
  "publishedAt": "2026-03-03T04:23:46.000Z",
  "site": "https://internals.rust-lang.org",
  "tags": [
    "[PreRFC] enum-variant-types",
    "PreRFC] enum-variant-types [language design",
    "Zulip",
    "Public view of rust-lang | Zulip team chat",
    "Rollup merge of #123648 - oli-obk:pattern_types_syntax, r=compiler-er… · rust-lang/rust@727c31a · GitHub",
    "Implement minimal, internal-only pattern types in the type system by oli-obk · Pull Request #120131 · rust-lang/rust · GitHub"
  ],
  "textContent": "I see this:\n\nPreRFC] enum-variant-types [language design\n\n> A more general version of this feature has been discussed under the name \"pattern types\".\n\nWhich after digging on the closed and unmerged MVP PR brings up this:\n\nZulip\n\n### Public view of rust-lang | Zulip team chat\n\nBrowse the publicly accessible channels in rust-lang without logging in.\n\nWhich was left @\n\n\n\nIn June 2023.\n\nThere's an older thread from 2018 which mentioned this and ended as:\n\n\n\nHowever I cannot find the newer thread, the one that mentioned it was about floating point rounding. Is it this commit: Rollup merge of #123648 - oli-obk:pattern_types_syntax, r=compiler-er… · rust-lang/rust@727c31a · GitHub\n\nDoes that mean it is in the current version of Rust? How do we use it?\n\n\n\nAhhh... It seems it is internal only and worked only for ranges: Implement minimal, internal-only pattern types in the type system by oli-obk · Pull Request #120131 · rust-lang/rust · GitHub\n\nSo basically, this is all still in flux and not currently being worked on? Not saying that is negative, I am just trying to understand where things are at the moment.",
  "title": "Subset enums"
}