We have described the Lexical Scoping concept very clearly using an example which
everybody can find it very helpful.
function tempFunc() {
var name = 'Laptop'; // name is a local variable created by tempFunc
function printName() { // printName() is the inner function, a closure
alert(name); // use variable declared in the parent function
}
printName();
}
tempFunc();
tempFunc() creates a local variable called name and a function called printName().
The printName() function is an inner function that is defined inside tempFunc() and
is available only within the body of the tempFunc() function. Note that the printName() function
has no local variables of its own. However, since inner functions have access to the
variables of outer functions, printName() can access the variable name declared in
the parent function, tempFunc().
Run the code and notice that the alert() statement within the printName() function successfully
displays the value of the name variable, which is declared in its parent function.
This is an example of lexical scoping, which describes how a parser resolves variable names
when functions are nested. The word lexical refers to the fact that lexical scoping uses the
location where a variable is declared within the source code to determine where that variable
is available. Nested functions have access to variables declared in their outer scope.
