I started using the Syntastic plugin for Vim, which will run a syntax checker on the current buffer and then indicate any lines which have errors. I can open up the list of errors as as a location list using :Errors, and then jump to the line of a given error by hitting Enter, which will jump to the line containing the error in my buffer.
I want to know how I can do the opposite. I want to go from a line in my buffer that is marked with having a syntax error to the corresponding entry in the location list, so that I can read the full error message in the list. How can I do this? I know that :ll [n] will jump to the nth error in the list, but often I will not know exactly which error number corresponds to the given line in the buffer. I cannot find a command that accepts a line number, rather than an error number, however.
I think that it's not possible, at least with default Vim commands or Syntastic.
But Syntastic actually echoes the error message associated with the current line in your command-line. This feature is enabled by default.