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JavaScript JavaScript Loops, Arrays and Objects Tracking Data Using Objects Using `for in` to Loop Through an Object's Properties

Objects For Loops

When entering a For loop to get an object do we need to type in the 'var' key word or can we leave it out? I noticed that it was left out on the 3rd video.

1 Answer

Steven Parker
Steven Parker
229,644 Points

It is always good practice to explicitly declare all variables.

And while you can get away without it in default mode, in strict mode attempting to create a variable implicitly will cause a syntax error.