Re: [Haskell-cafe] Couple of questions about let within do

11 Aug 2010


      So all the Xs would be in scope at s6. Important point.

Thanks,

Michael

--- On Tue, 8/10/10, Alex Stangl <alex@stangl.us> wrote:

From: Alex Stangl <alex@stangl.us>
Subject: Re: [Haskell-cafe] Couple of questions about *let* within *do*
To: "michael rice" <nowgate@yahoo.com>
Cc: "Tillmann Rendel" <rendel@Mathematik.Uni-Marburg.de>, haskell-cafe@haskell.org
Date: Tuesday, August 10, 2010, 2:21 PM

On Tue, Aug 10, 2010 at 11:01:28AM -0700, michael rice wrote:
...
Hi all,
Then,
   do s1
      s2
      let x1 = e1
          x2 = e2
      s3
      s4
      let x3 = e3
          x4 = e4
      s5
      s6
becomes
   do s1
      s2
      let x1 = e1
          x2 = e2 in do s3
                        s4
      let x3 = e3
          x4 = e4 in do s5
                        s6?
    do s1
       s2
       let x1 = e1
           x2 = e2
       in do s3
             s4
             let x3 = e3
                 x4 = e4
             in do s5
                   s6

HTH,

Alex