[fix] When called in a loop, the output is repeated

src/lib/compressor.ts

@@ -37,6 +37,7 @@ function compress(config?: globals.IConfig) {
       writers = globals.writers,
       output = globals.output,
       dest = globals.config.dest,
+      clear = globals.clear,
       version = globals.config.version,
       license = globals.config.license;
 
@@ -127,7 +128,7 @@ function compress(config?: globals.IConfig) {
             .catch(error => reject(error));
         });
       }
-
+      clear();
       resolve(output.join('\n'));
     });
   });

src/lib/generateoutput.ts

@@ -1,7 +1,5 @@
 import globals = require('./globals');
 
-var output = globals.output;
-
 function removeEmptyStringsFromEnd(output: Array<string>) {
     while (!output[output.length - 1]) {
         output.pop();
@@ -13,8 +11,10 @@ function removeEmptyStringsFromEnd(output: Array<string>) {
  * function, building the output array.
  */
 function generateOutput() {
+    var output = globals.output;
     var writers = globals.writers,
         previousLine = '';
+
 
     writers.forEach((writer) => {
         previousLine = writer.write(output, previousLine);

src/lib/globals.ts

@@ -32,6 +32,11 @@ export interface IConfig {
    * license will be replaced with the version.
    */
   license?: string;
+
+  /**
+   * Clear global cache var
+   */
+  clear?: Function;
 }
 
 export interface IObject<T> {
@@ -85,6 +90,15 @@ export function initialize(cfg: IConfig) {
   return config;
 }
 
+/**
+ * Clear cache
+ */
+export function clear() {
+  writers = [];
+  output = [];
+  imports = {};
+}
+
 export var config: IConfig,
   writers: Array<Writer> = [],
   output: Array<string> = [],