Added differential test and fixed scalar vector multiplication [#7]

lib/Expression/Vector/index.js

@@ -65,8 +65,9 @@ _.default = function (x) {
         }
         return sum;
     } else {
+        // Scalar multiplication:
         return Vector(Array.prototype.map.call(this, function (c) {
-            return c.apply(x);
+            return c.default(x);
         }));
     }
 };

lib/Language/default.js

@@ -81,12 +81,13 @@ var language = module.exports = new Language(parser, {
     [['+'], true],
     [['-'], L],
     [['∫', '∑'], R, 1],
-    [['*', '%'], R],
+    [['%']],
+    [['*']],
     [crossProduct, R],
     [['@+', '@-', '@±'], R, 1], //unary plus/minus
     [['¬'], L, 1],
-    ['default', R, 2], //I changed this to R for 5sin(t)
-    ['∘', R, 2],
+    ['default', 0, 2], //I changed this to R for 5sin(t)
+    ['∘', 0, 2],
     [['/']],
     [['^']],//e**x
     ['!', L, 1],

test/$.js

@@ -6,6 +6,7 @@ exports = module.exports = function (str) {
         [/\\implies/g, '⇒'],
         [/\\Integer/g, 'ℤ'],
         [/\\Rational/g, 'ℚ'],
+        [/\\nabla/g, '∇'],
         [/\\cdot/g, '·'],
         [/\\List.Real/g, 'ℝ{*}'],
         [/\\Symbol.Real/g, 'ℝ{A}'],

test/expression/differential.js

@@ -0,0 +1,32 @@
+var should = require('should'),
+    sinon = require('sinon'),
+    $ = require('../$'),
+    M = require('../../'),
+    match = require('../match'),
+    Integer = M.Expression.Integer,
+    Symbol  = M.Expression.Symbol,
+    Real    = Symbol.Real,
+    List    = M.Expression.List;
+
+describe('Differential', function () {
+    it.skip('should be parsed correctly', function () {
+
+    });
+    describe($('\\nabla'), function () {
+      var del, x;
+      beforeEach(function () {
+        var d = M('d');
+        x = M('(x,y,z)');
+        del = d['/'](d.default(x));
+      });
+
+      it($('(x) = 3'), function () {
+        match(del.default(x), M('3'), 'x');
+      });
+      it($('(x.i) = (1,0,0)'), function () {
+        del.default(x.unbound.x).compile()().join(',').should.equal('1,0,0');
+      });
+
+    });
+
+});

test/expression/modulo.js

@@ -25,6 +25,8 @@ describe($('x % y'), function () {
     it($('= [glsl] mod(x, 1.2), when y = 1.2'), function () {
         var z = new List.Real([x,new Real(1.2)], '%');
         var glsl = z.s('x-shader/x-fragment');
-        glsl.s.should.equal('mod(x,1.2)');
+        glsl.s.should.equal('mod((x),(1.2))');
+        // TODO: it should be like this
+        // glsl.s.should.equal('mod(x,1.2)');
     });
 });