used binary search on string indices

[bjarthur]

any reason not to use the much faster searchsorted instead of findfirst for At on a dimension whose indices are String? tests pass locally and my application code is 2x faster.

[rafaqz]

No reason I cant remember what even failed to have a type restriction there.

I think searchsorted just needs < and <= defined? Can anything be considered "ordered" without that?

Maybe we can just delete all of those types.

We can just state in the docs that Ordered lookup contents must define <. The automatic detection for it runs issorted already anyway, which must also use <.

[codecov-commenter]

Codecov Report

Merging #560 (64cf739) into main (b9162e1) will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #560      +/-   ##
==========================================
+ Coverage   88.06%   88.07%   +0.01%     
==========================================
  Files          40       40              
  Lines        3326     3329       +3     
==========================================
+ Hits         2929     2932       +3     
  Misses        397      397              

Files	Coverage Δ
src/LookupArrays/selector.jl	87.82% <ø> (ø)

... and 3 files with indirect coverage changes

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[rafaqz]

Well that failed on Symbol... maybe we can go back to just adding String, or AbstractString and work this out more systematically later.

[rafaqz]

Thanks!