Appendix C. JavaScript Global Properties
In addition to the global objects, there are a few simple global properties made available to your programs as well.
Table C.1. List of Properties
Property Name | Support | Description |
---|---|---|
| CH1+, FF1+, IE4+, NN4+, O3+, SF1+ | A number representing infinity. |
| CH1+, FF1+, IE4+, NN4+, O3+, SF1+ | Returns a special value that indicates something is not a number. |
| CH1+, FF1+, IE5.5+, NN4+, O3+, SF1+ | A value indicating an identifier is not defined. |
Infinity
Standard: JavaScript 1.3+, JScript 3.0+, ECMAScript 1.0+
Support: Google Chrome Beta+, Firefox 1.0 (Gecko 1.7)+, Internet Explorer 4.0+, Netscape Navigator 4.0+, Opera 3.0+, Safari 1.0+
Syntax
Infinity
Description
A number representing infinity. Both Infinity and NaN are members of the Number object.
Example
<script> var myVal = Infinity*Infinity; document.write(myVal + "<br />"); // Infinity myVal = 1/Infinity; // Should be zero document.write(myVal); // 0 </script>
NaN
Standard: JavaScript 1.3+, JScript 3.0+, ECMAScript 1.0+
Support: Google Chrome Beta+, Firefox 1.0 (Gecko 1.7)+, Internet Explorer 4.0+, Netscape Navigator 4.0+, Opera 3.0+, Safari 1.0+
Syntax
NaN
Description
Returns a special value that indicates something is not a number. Both Infinity and NaN are members of the Number object.
Example
<script> document.write(NaN); // NaN </script>
undefined
Standard: JavaScript 1.3+, JScript 5.5+, ECMAScript 1.0+
Support: Google Chrome Beta+, Firefox 1.0 (Gecko 1.7)+, Internet Explorer 5.5+, Netscape Navigator 4.0+, ...
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