How can I make JavaScript be as strict a Java? (types declaration, requiring "let" before declaration...)

Hiya there! I dunno much about Java but i know enough to answer your question. Many people would say that JavaScript has nothing to do with Java but JavaScript is changin' and the new syntaxes for OO for JavaScript pretty much looks and feels like java except for implementing data types with every variables. Both languages have their own version of "strict" mode. In order to operate in strict mode , you've to declare use strict; in the beginning of script. This type of style of writing JS codes is not so popular 'coz its only there in JavaScript for a sole reason i.e., compatibility with older version of JavaScript. Also it lets you write secure JavaScript code.

Now regarding Text Editors, I actually use 4 text editors from Jetbrains (RubyMine, WebStorm, IntelliJ, PyCharm). And all of 'em feels kinda same to me. They are great for professional and big projects but not for learning. Sometimes i like ligh weight IDE like Sublime Text 3. Webstorm is as great as IntelliJ and so are RubyMine ad PyCharm. But you can achieve everything else with your command line. I want to do everything with my terminal , thats the only thing im comfy with.

JavaScript is not a compiled language but there are tools that are emerging nowadays which compiles JS for faster performance and minifying of files and they also transpiles in native/document JavaScript. Exactly like TypeScript or Babel or Webpacks or Gulp or Grunt. I hope i've answered your questions.

~ Ari

ES 6 is trying to help developers be more OO with Javascript even though it is all syntactical sugar. I suggest looking into TypeScript.