I recently ran some of my JavaScript code through a linting tool and encountered an error that indicated a missing ‘use strict’ directive. After including ‘use strict’; at the beginning of my script, the error went away. However, I couldn’t find much information about what this directive does or its significance. Could someone explain what ‘use strict’; means, its implications, and whether it’s applicable in modern browsers?
‘use strict’ is a directive that was introduced in ECMAScript 5 to enable a stricter subset of JavaScript. It serves to enforce more rigorous error checking and helps prevent common JavaScript pitfalls. In strict mode, you cannot accidentally create global variables, assign values to read-only properties, or delete undeletable properties, among other things. This leads to cleaner and more secure code. While modern JavaScript environments support it, ‘use strict’ improves the transition to ES6 modules, which are strict by default, offering better performance and debugging.
yeah, ‘use strict’ helps by catching silent errors and making the code more predictable. It disallows certain syntax that might be tricky to debug later. Also helps in using reserved keywords safely. it’s like a “guard”. Most browsers and environments have good support for it, so it’s generally advisable to use.