bug fixed & add os.platform

module/fib.cpp

@@ -10,4 +10,18 @@ extern "C" nasal_ref fib(std::vector<nasal_ref>& args,nasal_gc& gc){
     if(num.type!=vm_num)
         return builtin_err("extern_fib","\"num\" must be number");
     return {vm_num,fibonaci(num.to_number())};
+}
+extern "C" nasal_ref quick_fib(std::vector<nasal_ref>& args,nasal_gc& gc){
+    nasal_ref num=args[0];
+    if(num.type!=vm_num)
+        return builtin_err("extern_fib","\"num\" must be number");
+    if(num.num()<2)
+        return num;
+    double a=1,b=1,res=0;
+    for(double i=1;i<num.num();i+=1){
+        res=a+b;
+        a=b;
+        b=res;
+    }
+    return {vm_num,res};
 }