fsprojects/RegexProvider — pull request #9 by marklam (2014-11-26 11:51:14+00:00)
Title: Prevent race condition on generalTypeSet.

Fix for Issue #8 - Hang in intellisense or shutdown due to HashSet corruption.
Two threads were modifying the HashSet, replaced with a ConcurrentDictionary<_, unit> because there's no ConcurrentSet.