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There is a new range syntax[1]. The release notes say it's rarely used, but makes code cleaner. In which cases would the syntax be useful? [1] https://golang.o

• thomasahle 12y ago
  If they added support for `range 10` to iterate 0-9 this would be useful for doing things a certain number of times. Now it's probably mostly useful for emptying iterators.
  • andrewchambers 12y ago
    Why do they need to add support for this? it already exists... https://github.com/bradfitz/iter/blob/master/iter.go https://github.com/bradfitz/iter/blob/master/iter.go
    • thomasahle 12y ago
      I don't think that would be considered good Go code. It's no shorter than writing out the 3-part for loop, and it is probably slower.
      • andrewchambers 12y ago
        what extra operations do you think range on a slice would do? The generated assembly is probably the same. Stylistically it is odd however.
• deleted 12y ago
  [deleted]
• dsymonds 12y ago
  One use case would be to exhaust a channel (that is, read everything off it until it is closed). Another might be to loop over something of a fixed size to correlate with a corresponding number of other things.
• Laremere 12y ago
  Here's a search of the go source for use of that: https://github.com/golang/go/search?p=3&q=%22for+range%22&type=Code&utf8=%E2%9C%93 https://github.com/golang/go/search?p=3&q=%22for+range%22&ty... Most of them are tests, but I see a couple genuine use cases: 1. Draining a channel until it closes. 2. Since range of a string gives utf8 runes, the RuneCountInString function in the utf8 package simply has an integer count, and does a range through the string increasing the count in every loop.
• rakoo 12y ago
  It's useful if you want to schedule a function every x seconds: for range time.Tick(1 * time.Second) { fmt.Println("tick") }