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update post: Closure and this - How are variables resolved within functions?

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bendtherules
2020-08-03 09:37:41 +05:30
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commit cb53ce7ea3
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@@ -160,6 +160,7 @@ These two methods are implemented on all types of environments (scope). Here is
| Environment Type | HasThisBinding() | GetThisBinding() | | Environment Type | HasThisBinding() | GetThisBinding() |
|--------|--------|---------------| |--------|--------|---------------|
| function | true/false | [[ThisValue]] |
| block scope | false | - | | block scope | false | - |
| module | true | undefined | | module | true | undefined |
| global | true | global object | | global | true | global object |
@@ -169,8 +170,8 @@ These two methods are implemented on all types of environments (scope). Here is
Now, back to the special resolving logic for `this`. It will do - Now, back to the special resolving logic for `this`. It will do -
Starting from the FunctionEnvironment (i.e. current function scope), Starting from the FunctionEnvironment (i.e. current function scope),
a. if `env.HasThisBinding()`, then return `env.GetThisBinding()` a. if `env.HasThisBinding()`, then return `env.GetThisBinding()`
b. else, move up to parent scope and repeat. b. else, move up to parent scope and repeat.
It will finally reach global scope, which always provides a `this` value (global object). For modules, it will stop at the module scope - whose `this` value is `undefined`. It will finally reach global scope, which always provides a `this` value (global object). For modules, it will stop at the module scope - whose `this` value is `undefined`.