Documentation lies

For various reasons, I want to get the extent of a particular expression in clang. Most AST objects in clang have a method along the lines of getSourceRange(), which, on inspection, returns start and end locations for the object in question. Naturally, it's the perfect fit (more or less), so I start using it. However, it turns out that the documentation is a bit of a liar. I would expect the end location to return the location (either file offset or file/line) of the end of the expression, give or take a character depending on whether people prefer half-open or fully closed ranges. Instead, it returns the location of the last token in the expression. Getting the true last token requires this mess: sm.getFileOffset(Lexer::getLocForEndOfToken(end, 0, sm, features)). Oh yeah, in case you couldn't have guessed, that causes it to relex the file starting at that point. For an idea of my current mood, pick a random image from Jennifer's recent post and you'll likely capture it.