Conditional Compilation Variables (JavaScript)

The following predefined variables are available for conditional compilation. If a variable is not true, it is not defined and behaves as NaN when accessed.

Warning

Conditional compilation is supported in all versions of Internet Explorer prior to Internet Explorer 11. Starting with Internet Explorer 11 Standards mode, and in Windows 8.x Store apps, conditional compilation is not supported.

Variables

Variable Description
@_win32 True if running on a Win32 system.
@_win16 True if running on a Win16 system.
@_mac True if running on an Apple Macintosh system.
@_alpha True if running on a DEC Alpha processor.
@_x86 True if running on an Intel processor.
@_mc680x0 True if running on a Motorola 680x0 processor.
@_PowerPC True if running on a Motorola PowerPC processor.
@_jscript Always true.
@_jscript_build Contains the build number of the JavaScript scripting engine.
@_jscript_version Contains the JavaScript version number in major.minor format.