os: File.SeekLine method

[StoicPerlman]

Wanted to see if there was any interest in this feature for os.File. Link below. Works just like Seek, except it steps by newlines.

Go is a big project, so before I went to the trouble of making a legit patch and making sure I don't break anything I wanted to see if there was interest in adding it.

https://github.com/StoicPerlman/fls

[davecheney]

No thank you. This doesn’t need to live in the standard library so I recommend you develop it in your own package.

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On 22 Dec 2017, at 14:53, Sam Kleiner ***@***.***> wrote: Wanted to see if there was any interest in this feature for os.File. Link below. Works just like Seek, except it steps by newlines. Go is a big project, so before I went to the trouble of making a legit patch and making sure I don't break anything I wanted to see if there was interest in adding it. https://github.com/StoicPerlman/fls — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub, or mute the thread.

[mvdan]

There are already pieces in the standard library for working with lines, such as https://golang.org/pkg/bufio/#Scanner. Or, if you need to go backwards and forwards instead of in a stream, you should instead split the input into a slice of lines with strings.Split or bytes.Split.

I also think that this is an unnecessary clutter of os.File. It absolutely doesn't need to know what a line is.

[StoicPerlman]

I figured that would be the answer. The ultimate goal for this is to be able to seek by any delimiter, but handling a > 1 byte delimiter adds some complexity that I didn't feel like doing before I knew if there was interest. I personally think seeking through a file for a delimiter is a pretty basic function.

The reason this was necessary is because nothing in bufio can seek line by line and return the position in the file. So Scanner could not meet my use case.

If anyone else stumbles on this and needs it feel free to checkout fls.