Improve function comment

Author: cjbj

lib/util.js

@@ -137,9 +137,10 @@ function getErrorMessage(errorCode) {
 
 module.exports.getErrorMessage = getErrorMessage;
 
-// assert it typically used in the beginning of public functions to assert preconditions
-// for the function to execute. Most commonly it's used to validate arguments lenght
-// and types and throw an error if they don't match what is expected.
+// assert is typically used at the beginning of public functions to assert
+// preconditions for the function to execute. Most commonly it is used to
+// validate the number of arguments and their types and throw an error if they
+// don't match what is expected.
 function assert(condition, errorCode, messageArg1) {
   if (!condition) {
     throw new Error(getErrorMessage(errorCode, messageArg1));