Crystal vs. Haskell vs. Java vs. JavaScript Comparison Chart

Every expression in Haskell has a type that is determined at compile time. All the types composed together by function application have to match up. If they don't, the program will be rejected by the compiler. Types become not only a form of guarantee, but a language for expressing the construction of programs. Every function in Haskell is a function in the mathematical sense (i.e., "pure"). Even side-effecting IO operations are but a description of what to do, produced by pure code. There are no statements or instructions, only expressions that cannot mutate variables (local or global) nor access state like time or random numbers. You don't have to explicitly write out every type in a Haskell program. Types will be inferred by unifying every type bidirectionally. However, you can write out types if you choose, or ask the compiler to write them for you for handy documentation.

JavaScript is a scripting language and programming language for the web that enables developers to build dynamic elements on the web. Over 97% of the websites in the world use client-side JavaScript. JavaScript is one of the most important scripting languages on the web. Strings in JavaScript are contained within a pair of either single quotation marks '' or double quotation marks "". Both quotes represent Strings but be sure to choose one and STICK WITH IT. If you start with a single quote, you need to end with a single quote. There are pros and cons to using both IE single quotes tend to make it easier to write HTML within Javascript as you don’t have to escape the line with a double quote. Let’s say you’re trying to use quotation marks inside a string. You’ll need to use opposite quotation marks inside and outside of JavaScript single or double quotes.