Feature idea: non-strict-mode

[Jamesernator]

This is just to expand on this comment.

Basically I'm proposing a policy that restricts what can run code that isn't in strict mode. For example non-strict-mode none would disable all attempts to run non-strict mode code (it would not upgrade it to strict mode as this changes behaviour).

This would include all possible sources of running non-strict mode code:

• <script> tags
• eval
• new Worker
• serviceWorker.register
• new Function
• importScripts()
• and any others I've missed

This could potentially allow engines to run on a slightly faster code path if they know that non-strict mode can never be run.