Should I Use Strict Mode

Strict mode restricts the use of error syntax and will not let the code run with errors in place. … We can’t run the code above in strict mode because this code will create a global variable badVariable if strict mode is off. Strict mode prevents this to prevent the creation of global variables accidentally.

Where do I put use strict?

Likewise, to invoke strict mode for a function, put the exact statement “use strict”; (or ‘use strict’; ) in the function’s body before any other statements.

What is the function form of use strict?

“use strict”; is a string literal expression place on the first line of the javascript file or the first line in a javascript function. If it’s put on the first line of the function, then the javascript strict mode will only be enforced in the function. …