A History Explorer that finds first/last/all occurrences of given text (think method signatures) and browse versions for integrated diffing of a given source file. It works with SCMs such as Subversion (SVN) and Visual SourceSafe (VSS) and can be extended via a plugin architecture to support other SCM's (think Git, Hg, TFS).
Currently it is a single form, and the intent is to allow relatively simple wrappers to be written for VS plug-ins, Windows Explorer extensions, Tortoise integrations, AnkhSVN/VisualSVN plug-ins, etc.
SVN url: https://differsion.svn.codeplex.com/svn
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