From: brian m. carlson Date: Sat, 08 Sep 2018 16:49:00 GMT Subject: Re: ordered string-list considered harmful, was Re: [PATCH v3] Allow aliases that include other aliases Message-ID: <20180908164900.GP432229@genre.crustytoothpaste.net> In-Reply-To: <20180907072353.GC172953@aiede.svl.corp.google.com> On Fri, Sep 07, 2018 at 12:23:53AM -0700, Jonathan Nieder wrote: > Ævar Arnfjörð Bjarmason wrote: > > If this turns out to be a common use-case perhaps the easiest way to > > support that would be to make the hashmap (optionally?) ordered, as Ruby > > 1.9 did with their hash implementation: > > https://www.igvita.com/2009/02/04/ruby-19-internals-ordered-hash/ > > That's about recording the order of insertion. I'm talking about > something much simpler: sorting an array (as preparation for emitting > it) and binary searching to find an entry in that array. If you want both a collection that is always sorted and has efficient lookup for an arbitrary entry, then a B-tree is probably a better choice. That's the primitive that Rust provides for that situation. -- brian m. carlson: Houston, Texas, US OpenPGP: https://keybase.io/bk2204