It might be usefull to add a max int parameter which stop clearing once this index is reached if this index is smaller than cap(s) so that this pattern could be used:
Can easily be done by reslicing before calling Clear.

oldLen := len(s)
s = DoDelete(s)
s = DoCompact(s)
s = DoFoo(s)
slices.Clear(s, oldLen)

This is because it can be a reasonable assumption to assume what was already free capacity was already zeroed, what would need to be rezeroed would just be the range between the old len and the new len (since we expect remanents from Delete and Compact to be remaining).

I don't yet see a need for a max parameter. Can't you simply write Clear(s[:max]) ?

I somehow overlooked that, this would require s[:len(s):max] but yes that solves the problem of over zeroing traling capacity.

There is already a builtin clear function coming in Go 1.21 (#56351, 4fe46ce). It zeroes the range 0:len(s) instead of len(s):cap(s) but you can always write clear(s[len(s):cap(s)]) to do that. Do we really need slices.Clear too?

sgtm ty