Case Sensitivity
When a language is fully case sensitive, every token in the language—including all identifiers and keywords—must be entered with the correct capitalization. For example, in case-sensitive languages, the statement:
If (x == 5) { x = 10; }
would cause an error because the keyword if
is
improperly capitalized as If
. Furthermore, in
case-sensitive languages, the following two statements would declare
two separate variables (one named firstName
and a
second one named firstname
):
var firstName = "doug"; var firstname = "terry";
The ECMA-262 specification, upon
which ActionScript is based, demands complete case sensitivity.
ActionScript, however, diverges from the standard in the area of case
sensitivity in order to maintain backward compatibility with Flash 4
movies. In ActionScript, the
keywords in Table 14.1 are case sensitive, but
identifiers are not. For example,
in the following, the onClipEvent
keyword is
incorrectly capitalized as onclipevent
and would
cause an error:
onclipevent (enterFrame) // Should be onClipEvent (enterFrame)
But unlike keywords, identifiers are not case sensitive in ActionScript, so the following statements assign a value to the same variable:
var firstName = "margaret"; var firstname = "michael"; trace(firstName); // Yields "michael" trace(firstname); // Also yields "michael" (the variables are the same)
Even internal identifiers, such as property names and function names, are not case sensitive in ActionScript. The following line would cause an ...
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