scanLines -- apply a function to each line of a file

• Usage:

  scanLines(f,fn)

• Inputs:
  • f
  • fn, the name of a file, or a list of names of files
• Outputs:
  • returns null unless the function uses break x with a non-null value for x, in which case scanning stops and x is returned immediately
• Consequences:

  • applies f to each line of the file(s)