In ES6, we can put the default values right in the signature of the functions.
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varcalculateArea=function(height =50, width =80){
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// write logic
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...
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}
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Template Literals
We can use a new syntax ${PARAMETER} inside of the back-ticked string.
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var name =`Your name is ${firstName}${lastName}.`
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Multi-line Strings in ES6
Just use back-ticks.
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let lorem =`Lorem ipsum dolor sit amet,
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consectetur adipiscing elit.
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Nulla pellentesque feugiat nisl at lacinia.`
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Arrow Functions
Arrow functions – also called fat arrow functions, are a more concise syntax for writing function expressions. They utilize a new token, =>, that looks like a fat arrow. Arrow functions are anonymous and change the way this binds in functions.
There are a variety of syntaxes available in arrow functions, of which MDN has a thorough list.
Basic Syntax with Multiple Parameters (from MDN)
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// (param1, param2, paramN) => expression
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// ES5
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varmultiplyES5=function(x, y){
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return x * y;
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};
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// ES6
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constmultiplyES6=(x, y)=>{return x * y };
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Curly brackets and return aren’t required if only one expression is present. The preceding example could also be written as:
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constmultiplyES6=(x, y)=> x * y;
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Parentheses are optional when only one parameter is present but are required when no parameters are present.