Nimble csv parse error

vishal-h · May 27, 2020, 1:21pm

Here is a simple csv
csv = ~s(name, name@email.com, prop1, 40, prop2, “A, B”, “p:q, x:y”) and parser is defined as
NimbleCSV.define(MyParser, separator: “,”, escape: “\”")

Now running the praser…
MyParser.parse_string(csv, skip_headers: false) gives the error

**** (NimbleCSV.ParseError) unexpected escape character " in ,**

What’s wrong here?

Thanks …

al2o3cr · May 27, 2020, 2:43pm

should instead be:

~s(name,name@email.com,prop1,40,prop2,"A, B","p:q, x:y")

The CSV parser does not want a space after , and explicitly looks for escape characters immediately preceded by a separator:

github.com

dashbitco/nimble_csv/blob/3e869aa945b5428e59f6a05222f1a36f0bd3eb7d/lib/nimble_csv.ex#L382


      
              offset = byte_size(var!(line))
              unquote(newlines_offsets)
              case var!(line), do: unquote(newlines_clauses)
            end
          end
          
          defmacrop separator_case() do
            clauses =
              Enum.flat_map(@separator, fn sep ->
                quote do
                  <<prefix::size(var!(pos))-binary, unquote(sep), @escape, rest::binary>> ->
                    escape(
                      rest,
                      "",
                      var!(row) ++ :binary.split(prefix, var!(separator), [:global]),
                      var!(state),
                      var!(separator),
                      var!(escape)
                    )
                end
              end)

vishal-h · May 27, 2020, 5:14pm

RFC https://tools.ietf.org/html/rfc4180 - Spaces are considered part of a field and should not be ignored.

Thanks for the quick response, Otherwise it would have taken a while to find this out!