A default constructor is one with no parameters. If you don't provide one for your class, the compiler will create on default constructor for your class. However if you do provide a constructor with or without any parameters then the compiler doesn't create a default constructor for you.
Very often while reviewing the code for my team, I will come across a semicolon at the start of JavaScript function as show below ; (function () { 'use strict'; ...and I often wondered what purpose it served. Guess what. It is an insurance to make sure your script works fine when all other scripts are merged together; The leading ; in front of immediately-invoked function expressions (iffe) is there to prevent errors when appending the file during concatenation to a file containing an expression not properly terminated with a ;. So there you go. Now you know what that little semicolon is doing there in your code.
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