__FB_JS__
Syntax
`__FB_JS__`
Description
Defined without a value at compile time when the JavaScript target is being used. This is normally selected by `fbc-js` or by the `-target js-asmjs` command line option. It can be used to compile parts of a program only for the browser/Emscripten target.
The JavaScript target also defines `__FB_LINUX__` for compatibility with Emscripten's POSIX-like runtime environment.
Example

    #IFDEF __FB_JS__
        print "JavaScript target"
    #ENDIF

Predefined Defines
See also
Compiling FB for JavaScript
Compiler Option: -target
Compiler Meta-Commands