by blake.mizerany:

I’ve been slowly working on migrating more of Heroku’s codebase over to Go. One of
my more Ruby-centric coworkers just wasted several hours today on Go’s lack of support
for this regular expression:

    var validRequest = regexp.MustCompile(`^/customer/(\w+)/(\w+)?authas=\1(&.*)?`)

After tweaking, I’ve narrowed it down to this minimal repro case:

   var r = regexp.MustCompile(`^(a).+\1`)

That works fine in Ruby:

$ irb
>> "abba".match(/^(a).+\1/)
=> #<MatchData "abba" 1:"a">

Why doesn’t this work in Go?

Not to look a gift horse in the mouth, but I’ll have a harder time getting co-workers
to adopt Go if such basic things from Ruby aren’t even supported.