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JavaScript

Posted by Benjamin Hedgepeth
Benjamin Hedgepeth
5,672 Points

Scope and context in JavaScript

I've read that scope and context within JavaScript are not the same thing. While reading the topic of scope in Wikipedia, it has generated some confusion. Clarification would be appreciated.

https://en.wikipedia.org/wiki/Scope_(computer_science)

"The term "scope" is also used to refer to the set of all entities that are visible or names that are valid within a portion of the program or at a given point in a program, which is more correctly referred to as context or environment."

I've only quoted what confused me. It would probably be best if those that are familiar to go to the source itself.

1 Answer

Steven Parker
Steven Parker
243,160 Points
Steven Parker
Steven Parker
243,160 Points

These quotes from the same article might be helpful.

Elsewhere in the article it says, "scope is a property of an identifier, and is fixed, while context is a property of a program, which varies by position."

It also says: Narrowly speaking, during execution a program enters and exits various scopes, and at a point in execution identifiers are "in context" or "not in context"

Just be aware that these terms are often interchanged, even where it may not be entirely appropriate. So be prepared to make allowances where you see these terms used.