JavaScript is a very function-oriented language. It gives us a lot of freedom. A function can be created at any moment, passed as an argument to anoth…
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This way the code is executed in the global scope:… It creates a function from a string, also in the global scope. So it can’t see local variables.… Instead, to eval the code in the global scope, use window.eval(code).… Or, if your code needs some data from the outer scope, use new Function and pass it as arguments.
“var” has no block scope.Variables, declared with var, are either function-scoped or global-scoped.… “var” tolerates redeclarations.If we declare the same variable with let twice in the same scope, that… Summary.There are two main differences of var compared to let/const:
var variables have no block scope… , their visibility is scoped to current function, or global, if declared outside function.
var declarations
Usually, special CSS classes and conventions are used to provide “component feel” – CSS scoping and DOM… CSS Scoping – to declare styles that only apply inside the Shadow DOM of the component.
It’s a bit beyond our scope now, but you can find its methods in the DataTransfer specification.… So most browsers allow seamless read/write access to the clipboard only in the scope of certain user
Errors that may occur during script processing and execution are out of scope for these events.… Such thing as “cookies” is out of our current scope, but you can read about them in the chapter Cookies
Module-level scope.Each module has its own top-level scope.… Resulthello.jsuser.jsindex.htmlIn the browser, if we talk about HTML pages, independent top-level scope… Modules have their own, local top-level scope and interchange functionality via import/export.
references the Lexical Environment from where it’s created (we covered that in the chapter Variable scope
we still shouldn’t forget that they are based on promises, because sometimes (e.g. in the outermost scope
For instance, we can rewrite the counter function example from the chapter Variable scope, closure to
Sometimes it’s ok to write .then directly, because the nested function has access to the outer scope.
It’s outside of our scope here, but here’s an example, and you can read more at https://developer.mozilla.org
Another special feature of Function Declarations is their block scope.
Scope – current variables.
Local shows local function variables.
Then, at some point, we stop using the user variable – it gets overwritten, goes out of scope… If the object that creates the FinalizationRegistry instance goes out of scope or is deleted, the cleanup
GDPR is not only about cookies, it is about other privacy-related issues too, but that is beyond our scope
revoke is separate from proxy, so that we can pass proxy around while leaving revoke in the current scope