add alias name

Author: peze

lib/semantic.js

@@ -821,6 +821,7 @@ class TypeChecker {
     assert.equal(ast.type, 'module');
     // 类型系统
     this.usedExternModel = new Map();
+    this.aliasNames = new Map();
     this.usedTypes = new Map();
     this.checkImports(ast);
     this.checkExtends(ast);
@@ -853,6 +854,7 @@ class TypeChecker {
     ast.conflictModels = this.resolveConflictModels(ast.usedExternModel);
     ast.usedTypes = this.usedTypes;
     ast.innerDep = this.innerDep;
+    ast.aliasNames = this.aliasNames;
     // save the final ast in checker
     this.ast = ast;
     return this;