Merge pull request #285 from null-a/deepcopy-ast-in-compile

Deep copy AST in compile

src/browser.js

@@ -22,13 +22,13 @@ packages.forEach(function(pkg) {
   pkg.headers.forEach(webppl.requireHeaderWrapper);
 });
 
+var extra = webppl.parsePackageCode(packages);
+
 function run(code, k, verbose) {
-  var extra = webppl.parsePackageCode(packages, verbose);
   return webppl.run(code, k, { extra: extra, verbose: verbose });
 }
 
 function compile(code, verbose) {
-  var extra = webppl.parsePackageCode(packages, verbose);
   return webppl.compile(code, { extra: extra, verbose: verbose });
 }
 

src/main.js

@@ -128,6 +128,14 @@ function applyCaching(asts) {
   });
 }
 
+function copyAst(ast) {
+  var ret = _.isArray(ast) ? [] : {};
+  _.each(ast, function(val, key) {
+    ret[key] = _.isObject(val) ? copyAst(val) : val;
+  });
+  return ret;
+}
+
 function compile(code, options) {
   var options = util.mergeDefaults(options, { verbose: false, generateCode: true });
 
@@ -144,7 +152,7 @@ function compile(code, options) {
 
   function _compile() {
     var programAst = parse(code, extra.macros);
-    var asts = extra.asts.concat(programAst);
+    var asts = extra.asts.map(copyAst).concat(programAst);
     var doCaching = _.any(asts, caching.transformRequired);
 
     if (options.verbose && doCaching) {

tests/browser/tests.js

@@ -6,6 +6,14 @@ QUnit.test('run', function(test) {
   });
 });
 
+QUnit.test('run twice', function(test) {
+  _.times(2, function() {
+    webppl.run('Enumerate(flip)', function(s, erp) {
+      test.ok(_.isEqual([false, true], erp.support().sort()));
+    });
+  });
+});
+
 QUnit.test('compile', function(test) {
   test.ok(_.isString(webppl.compile('1 + 1')));
 });