Other differences between Navigator and Internet Explorer 3.0 are
small details about the way values are computed and printed:
- The for/in statement in IE 3.0 does not
always enumerate the same object properties that Navigator
does. It does enumerate all user-defined properties, which is
its primary function. But predefined properties of built-in
objects are not always listed.
- The && and || operators behave somewhat differently in
an untyped langauge, the difference is usually irrelevant.
When the first operand of the && operator
evaluates to true, then the operator
returns the value of the second operand in Navigator. In
Internet Explorer, this second operand is first converted to a
Boolean value, and that value is returned. Thus the
evaluates to 10 in Navigator but to
true in Internet Explorer. This may seem
langauge, it rarely matters. The &&
operator is almost always used in a Boolean context, such as
the expression of an if statement, so even
when Navigator returns a value like 10,
that value will be immediately converted to the Boolean value
true within that context. The same
evaluation difference occurs when the first operand of the
|| operator evaluates to
- In Internet Explorer 3.0, Boolean values implicitly are
converted to strings differently than they are in Navigator.
The value true is converted to the string
-1, and the value false
is converted to the string 0. If you
actually want them to be converted to the strings "true" and
"false", you must convert them explicitly by adding them to
the empty string.
- User-defined function values are also converted to strings
differently in IE 3.0. In Navigator, functions are converted
to a string that includes the complete body of the function.
In fact, you can even use eval() function
to define the function in some other window. This does not
work in Internet Explorer, which omits the function body
from its string representation of functions.