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Gustavo Winter
Gustavo Winter
Courses Plus Student 27,382 Points

When should i use 'use strict' ?

I finished "Introducing ES2015" , all over the course, i see at the top of the page 'use strict'

My doubt is, when should i use this?

1 Answer

Steven Parker
Steven Parker
229,952 Points

Some people would say "always", since it primary makes bad programming practices into fatal errors. Those same people would say that not using it is "sloppy mode". :wink:

For details on what differences it makes, see this MDN page on Transitioning to strict mode.