[("tests/examples/Default21.hs:1:12-22: Warning: Use fst\nFound:\n \\ (a, b) -> a\nPerhaps:\n fst\n",[Replace {rtype = Expr, pos = SrcSpan {startLine = 1, startCol = 12, endLine = 1, endCol = 23}, subts = [], orig = "fst"}])]