last_loc :: SrcSpan, -- pos of previous token
last_offs :: !Int, -- offset of the previous token from the
-- beginning of the current line.
-- \t is equal to 8 spaces.
last_len :: !Int, -- len of previous token
last_loc :: SrcSpan, -- pos of previous token
last_offs :: !Int, -- offset of the previous token from the
-- beginning of the current line.
-- \t is equal to 8 spaces.
last_len :: !Int, -- len of previous token