Question

This is C# version:

public static IEnumerable<string> ReadLinesEnumerable(string path) {
  using ( var reader = new StreamReader(path) ) {
    var line = reader.ReadLine();
    while ( line != null ) {
      yield return line;
      line = reader.ReadLine();
    }
  }
}

But directly translating needs a mutable variable.

Answer 1

open System.IO

let readLines (filePath:string) = seq {
    use sr = new StreamReader (filePath)
    while not sr.EndOfStream do
        yield sr.ReadLine ()
}