SML uncaught exception “Use failed: Io: openIn failed on…”

Question

I am new with SML/programming/emacs/all the stuff and when I do the first homework from coursera class I have the old story regarding this error:

  [opening is_older.sml]
  [use failed: Io: openIn failed on "is_older.sml", Win32TextPrimIO:openRd: failed]
  uncaught exception Error
  raised at: ../compiler/TopLevel/interact/interact.sml:24.14-24.28

I tried all the possible things found on the forums, topics, like: path,checking any misspelled name of sml file, coding-I put several codes, savings, etc. The only thing I did not made was to custom Emacs and I didn't verify if the SML-mode is working properly since 2 days ago Emacs and SML/NJ were installed.

The last code I wrote - but anyway is not important because it doesn't matter which code is, I have the same error - is this:

      fun is_older ((x1,y1,z1), (x2,y2,z2)) =
        if z1 < z2
        then true
        else
          if x1 = x1 andalso y1 = y2 andalso z1 < z2
          then true
          else false;

If you open a Windows command prompt [or PowerShell session], navigate to the location of is_older.sml and type the command "sml", what happens? What happens if you type M-x run-sml in Emacs? — ben rudgers

Andreas Rossberg Andreas Rossberg · Accepted Answer · 2014-10-17T06:49:07

[use failed: Io: openIn failed on "is_older.sml", Win32TextPrimIO:openRd: failed]

This sounds like like it simply didn't find the file. Maybe you misspelled the name, or it's in a different directory?

SML uncaught exception “Use failed: Io: openIn failed on…”

1 Answers