Lab 2: SML, Flex & Bison, and Automake & Autoconf

1. Flex and Bison
   • This is a Flex and Bison example provided for you to verify your Problem Set 2.
   • Download parser.tar.gz
   • Ungzip and untar parser.tar.gz

       $ gzip -cd parser.tar.gz | tar xvf -
       $ cd parser
       

   • Follow the compilation instructions at the top of parser.yy
   • You may change the grammar in parser.yy to verify your PS2.
2. Automake & Autoconf
   • This is a simple demonstration to show you how to use GNU Automake and Autoconf.
   • Create Makefile.am

       bin_PROGRAMS = parser
       parser_SOURCES = parser.yy scanner.ll
       AM_YFLAGS = -d
       

   • Run autoscan to create configure.scan
   • Rename configure.scan to configure.in
   • Edit configure.in, fill in AC_INIT, added AM_INIT_AUTOMAKE after AC_INIT, and add AM_PROG_LEX and AC_PROG_YACC after AC_PROG_CC.
   • Run autoheader to create config.h.in
   • Run aclocal to create aclocal.m4
   • $ touch NEWS README AUTHORS ChangeLog
   • Edit AUTHORS

       WeeSan Lee <weesan@cs.ucr.edu>
       

   • Run automake -a
   • Run autoconf
   • Run configure
   • Run make
   • To distribute your code, run make dist, which will generate parser-0.0.1.tar.gz in this case.
3. SML Basics
   • How to start sml?
     • On any lab machine, run sml from /usr/csshare/bin/sml
     • Alternatively, add /usr/csshare/bin to your path and run sml
   • How to run sml code in a batch?
     • Edit lab2.sml
     • Run sml
     • At the dash prompt, type: use "lab2.sml"
   • Emacs sml-mode
     • Download Emacs sml-mode from http://www.iro.umontreal.ca/~monnier/elisp/sml-mode-4.0.tar.gz
     • $ mkdir -p ~/share/emacs
     • $ cd ~/share/emacs
     • $ gzip -cd ~/sml-mode-4.0.tar.gz | tar xvf -
     • Add the following lines to ~/.emacs for automatically switching mode when editing .sml files and turning on syntax highlighting:

         ; load sml-mode setup code
         (load "~/share/emacs/sml-mode-4.0/sml-mode-startup")
         (add-hook 'sml-mode-hook 'turn-on-font-lock)
         

     • $ emacs lab2.sml
     • Press C-c C-b to run your editing code with sml
4. SML Exercises
   1. Write a function max of type int list -> int that returns the largest element of a list of integers. Your function need not behave well if the list is empty. Hint: Write a helper function maxhelper that takes as a second parameter the largest element seen so far. Then you can complete the exercise by defining fun max x = maxhelper(tl x, hd x);
   2. Write a function to test whether an element is a member of a set. For example isMember(x, l) would return true if x is an element in the list l, and false otherwise.
   3. Write a function to construct the union of two sets, ie. union(x, y) where both x and y are lists, and union(x, y) would return a list of unique elements, each of which belongs to either list x or y.
   4. Write a function to construct the intersection of two sets. ie. intersect(x, y) where both x and y are lists, and intersect(x, y) would return a list of unique elements, each of which belongs to both list x and y.