Parser Combinators Beat Regexes

Parser combinators are great until you need to parse something real, like CSV with embedded newlines and Excel quotes. That’s when you reach for the reliable trio: awk, duct tape, and prayer.

I don't follow why parser combinators would be a bad tool for CSV. It seems like one would specify a CSV parser as (pardon the pseudocode):

  separator = ','
  quote = '"'
  quoted_quote = '""'
  newline = '\n'
  plain_field = sequence(char_except(either(separator, quote, newline)))
  quoted_field = quote + sequence(either(char_except(quote), quoted_quote)) + quote 
  field = either(quoted_field, plain_field)
  row = sequence_with_separator(field, separator)
  csv = sequence_with_separator(row, newline)

Seems fairly natural to me, although I'll readily admit I haven't had to write a CSV parser before so I'm surely glossing over some detail.

I think GP was sarcastic. We have these great technologies available but people end up using duct tape and hope anyway.