on Thu Jun 23 2016, Xiaodi Wu <[email protected]> wrote: > On Wed, Jun 22, 2016 at 10:24 PM, Joe Groff via swift-evolution < > [email protected]> wrote: > >> Proposal link: >> https://github.com/apple/swift-evolution/blob/master/proposals/0077-operator-precedence.md >> >> Hello Swift Community, >> >> The review of SE-0077: "Improved operator declarations" ran from May >> 17...23. On June 22, 2016, the core team decided to *return* the first >> version of this proposal for revision. The core design proposed is a clear >> win over the Swift 2 design, but the core team feels that revisions are >> necessary for usability and consistency with the rest of the language: >> >> - The proposed associativity(left) and precedence(<) syntax for >> precedence group attributes doesn’t have a precedent elsewhere in Swift. >> Furthermore, it isn’t clear which relationship < and > correspond to in >> the precedence syntax. The core team feels that it’s more in the character >> of Swift to use colon-separated “key-value” syntax, with associativity, >> strongerThan, and weakerThan keyword labels: >> >> >> precedencegroup Foo { >> >> associativity: left >> >> strongerThan: Bar >> >> weakerThan: Bas >> >> } >> >> >> -If “stronger” and “weaker” relationships are both allowed, that would >> enable different code to express precedence relationships in different, >> potentially confusing ways. To promote consistency and clarity, the core >> team recommends the following restriction: Relationships between precedence >> groups defined within the same module must be expressed exclusively in >> terms of strongerThan. weakerThan can only be used to extend >> the precedence graph relative to another module’s groups, subject to the >> transitivity constraints already described in the proposal. This enforces a >> consistent style internally within modules defining operators. >> >> > This definitely looks cleaner, but the terminology "stronger" and "weaker" > is pretty non-standard. Typically, precedence is said to be above or below > (equivalently, over or under, higher or lower) or, alternatively, before or > after.
Although I was the one who suggested “stronger/weaker”, on reflection I think “higher/lower” are the most standard terms here. -- Dave _______________________________________________ swift-evolution mailing list [email protected] https://lists.swift.org/mailman/listinfo/swift-evolution
