crguezl/nathanuniversityexercisespl

Solutions to the exercises in Nathan's course

#Integrate your parser

Next, integrate your Scheem parser and Scheem interpreter.

First make a minor update to your parser so that it detects numbers. You want inputs like 5 to parse to the number 5 rather than the string 5.

Once you've got that done, you should be able to parse inputs like (+ 2 (* 3 4)) into a JavaScript form that is ready for passing along to your evalScheem.

#Downloading your parser code

Now in your local copy of simpletest.html add a line to load your parser. I organized the files as Scheem/parser.js and Scheem/test/simpletest.html so my extra line in Scheem/test/simpletest.html looks like this:

        <script src="../parser.js"></script>

#Unit testing the parser

Now we can start writing tests for the parser. Here are a couple examples:

      suite('parse', function() {
          test('a number', function() {
              assert.deepEqual(
                  SCHEEM.parse('42'),
                  42
              );
          });
          test('a variable', function() {
              assert.deepEqual(
                  SCHEEM.parse('x'),
                  'x'
              );
          });
      });
      evalScheemString

Now that you have your parser and interpreter working together, you can make a single function that does everything. Create a new function evalScheemString that takes a string and an environment and then parses and interprets the Scheem expression.

Integrate your parser into your browser test page. Write tests of all the features of your parser and make sure they pass. Add in the evalScheemString function. Write some tests for it, too.