Hi, Thank you for the response.
My issue is not really about append but can be illustrated by this : https://play.golang.org/p/YZlo1mqGDLz On Saturday, October 26, 2019 at 2:27:06 PM UTC+2, Gert wrote: > > Sorry, the performance cost is to high. But you can practice a few > programming habits that can prevent this, like use x = append(x, y) and > never x = append(y, x) Basically we only need a Go proverb bible mentioned > in one of Rob Pike's talks and we will be fine :) > > On Saturday, October 26, 2019 at 1:40:23 PM UTC+2, atd...@gmail.com wrote: >> >> Hello, >> >> I've just realized that slices were much more delicate to use than >> initially thought. The main issue is that when slices share the same >> backing array, it is too easy to inadvertently have an unprotected >> concurrent Read/Write if one is not careful. >> That can easily happen for a struct that has a field of type slice for >> instance. The object might be safe to copy and pass around to multiple >> goroutine but reading a value from the slice field can still be problematic >> if there is a write at the same time on one of the object's slice field. >> >> This is not a proposal but for later, would it make sense to have slices >> become real snapshots (immutable) or copy/allocate on mutation? >> It will probably have perf repercussions. >> >> Or alternatively a tool that alerts of cases where there are such case of >> unprotected concurrent use (perhaps the race detector already does this) >> >> Even better is if that's a non argument because the cases where it's >> happen in real world code is sparse but I must admit that it took me a long >> time to think about this and now, I'm worried that it's a mistake too >> easily made. >> >> Also, I do not remember the specifics of the map code, but what happens >> for a map of slices? Do the slice elements share the backing array? >> >> >> >> -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/cf96053e-1209-459a-bc80-830690da80b0%40googlegroups.com.
