Sometimes it would be nice to be able to say something like: (git|svn|hg|etc) diff Foo.c:main (git|svn|hg|etc) log log Foo.c:main to see the changes made to a specific function within a source file since the last commit, or the complete history of changes. My question is two-fold: Does something exist that does this? Would such a tool be practical? It would have to do some simple parsing of the code at each revision in order to compare different versions of the function; would the overhead be too much for it to be efficient?