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	by skldj28d2 728 days ago
	Basically every custom data structure right now has some custom implementation of iterators. This will set a standard and make them usable with range loops. Even simple library methods like scanner.Scan, strings.Split, regex.FindAll or sql.Query should return iterators.

3 comments

klabb3 727 days ago

> strings.Split, regex.FindAll

But they already do, slices are iterables, and the input is bounded. Plus you have lots of other benefits like indexability. What need would it solve?

> scanner.Scan, sql.Query

Right, these are not suitable for slices because they’re unbounded. But still, what’s the use case? You still have roughly the same amount of code, no? Even the same noisy if err != nil checks. Can you provide a snippet that highlights the benefits?

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Zababa 727 days ago

https://github.com/golang/go/issues/61405#issuecomment-16388...:

> Can you provide more motivation for range over functions?

> If the results can be generated one at a time, then a representation that allows iterating over them scales better than returning an entire slice. We do not have a standard signature for functions that represent this iteration. Adding support for functions in range would both define a standard signature and provide a real benefit that would encourage its use.

> There are also functions we were reluctant to provide in slices form that probably deserve to be added in iterator form. For example, there should be a strings.Lines(text) that iterates over the lines in a text.

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38 728 days ago

> scanner.Scan, strings.Split, regex.FindAll or sql.Query should return iterators

Will never happen. Best you can hope for is new functions

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skldj28d2 728 days ago

I know. There are already proposals to add new functions to many of these packages that return iterators.

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38 727 days ago

no there arent

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skldj28d2 727 days ago