I didn't know, that a variable implicitly declared within a function is a global variable.
For example,
function foo() {
g= 17;//it's global, will be visible outside the function after the function will be executed
var x = 17;//local, not visible outside the function
}
foo();
println(g);//17
println(x);//undefined
another rule(UPDATE:known browsers do not support it) : Depending on the system in which JavaScript is embedded, other objects whose scopes enclose the function currently executing (if any) are searched, starting from the innermost object, for a property identified by the simple name. If found, the simple name's scope is the object containing the property.
I understood the rule as it is not nesessary to pass local variables as parameters to calling function, but the calling function can see parents variables.
function foo() {
var x = 17;//local, but should be visible in calling function according to the rule
foo1();
}
function foo1() {
println(x);//should be 17 if called from foo, but known browsers do not support it.
}
However as it was pointed by
Nitin Reddy Katkam, neither Firefox's nor Internet Explorer's nor Safari implementation of Javascript support this rule.
posted @ Friday, September 05, 2008 12:39 PM