Question

I’m having a little difficulty navigating all the haskell docs..

I want to call the file function from the Text.BibTeX.Parse module in haskell, but I can’t figure out where to get the Parser argument:

file :: Parser [T]

I know it comes from the Parsec module, but when I look there, I have no idea what the numbers variable in the example code of parseFromFile refers to:

main    = do{ result <- parseFromFile numbers "digits.txt"
              ; case result of
                  Left err  -> print err
                  Right xs  -> print (sum xs)
              }

Answer 1

You don’t need to produce a Parser argument to use file: it already is a Parser! The variable numbers in the Parsec documentation is probably standing in for whatever parser you want to run on the text in "digits.txt". So, in your case, that’s the file parser; you’d use file instead of numbers.