Possible to enable "strict mode" in FireBug and Chrome's console?
console, javascript, strict-mode
Solution
The firebug console works by wrapping all the code in an "eval" call so the first statement in your script is no longer "use strict" - hence it is disabled. You could try wrapping your code in a function to enforce "use strict" for that particular function but the best solution I know of is to skip the console and test straight in the page itself.
Problem
With this page: ``` <!DOCTYPE html> <html> <head> <script> "use strict"; var foo = 2; delete foo; </script> </head> <body></body> </html> ``` Firebug console gives: ``` applying the 'delete' operator to an unqualified name is deprecated >>> foo ReferenceError: foo is not defined foo ``` But then this is successful: ``` >>> var bar = 2; undefined >>> delete bar; true ``` Even if you comment out `delete foo;` so that the script does not break, deleting `bar` is still successful despite the fact it "is a property of a Global object as it is created via variable declaration and so has DontDelete attribute": ``` >>> foo 2 >>> delete foo false >>> var bar = 2; undefined >>> delete bar true ``` Is it possible to enable "strict mode" in FireBug and or Chrome's console?