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JavaScript Getting Started With ES2015 Defining Variables With let and const Using let with for Loops

Posted by John Cannon
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John Cannon
Full Stack JavaScript Techdegree Student 3,161 Points

Before ES6

Ok I understand why we should use let instead of var in a for loop. But before ES6 how did programmers solved the issue of var in a for loop since there was no let

Thanks

2 Answers

Steven Parker
Steven Parker
229,644 Points
Steven Parker
Steven Parker
229,644 Points

The classic technique was to use an immediately invoked anonymous function to create what is known as a "closure". That gave the variable created with "var" a unique and persistent scope similar to what you get with "let".

John Cannon
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John Cannon
Full Stack JavaScript Techdegree Student 3,161 Points

Can you give me an example

John Cannon
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John Cannon
Full Stack JavaScript Techdegree Student 3,161 Points
John Cannon
.a{fill-rule:evenodd;}techdegree
John Cannon
Full Stack JavaScript Techdegree Student 3,161 Points

Thanks