michael@0: function add(a, b, k) {
michael@0:   var result = a + b;
michael@0:   return k(result);
michael@0: }
michael@0: 
michael@0: function sub(a, b, k) {
michael@0:   var result = a - b;
michael@0:   return k(result);
michael@0: }
michael@0: 
michael@0: function mul(a, b, k) {
michael@0:   var result = a * b;
michael@0:   return k(result);
michael@0: }
michael@0: 
michael@0: function div(a, b, k) {
michael@0:   var result = a / b;
michael@0:   return k(result);
michael@0: }
michael@0: 
michael@0: function arithmetic() {
michael@0:   add(4, 4, function (a) {
michael@0:     // 8
michael@0:     sub(a, 2, function (b) {
michael@0:       // 6
michael@0:       mul(b, 3, function (c) {
michael@0:         // 18
michael@0:         div(c, 2, function (d) {
michael@0:           // 9
michael@0:           console.log(d);
michael@0:         });
michael@0:       });
michael@0:     });
michael@0:   });
michael@0: }
michael@0: 
michael@0: // Compile with closure compiler and the following flags:
michael@0: //
michael@0: //     --compilation_level WHITESPACE_ONLY
michael@0: //     --source_map_format V3
michael@0: //     --create_source_map code_math.map
michael@0: //     --js_output_file    code_math.min.js
michael@0: //
michael@0: // And then append the sourceMappingURL comment directive to code_math.min.js
michael@0: // manually.