dart: trim a string

Signed-off-by: Ayush Dubey <[email protected]>

Author: Ayushd70

dart/trim.dart

@@ -0,0 +1,6 @@
+void main() {
+  String message = "      Hello       ";
+  print("***" + message.trimRight() + "***");
+  print("***" + message.trimLeft() + "***");
+  print("***" + message.trim() + "***");
+}