NativeScript Core
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C Global Variables

C global variables are available in JavaScript as JavaScript global variables. Consider the following C declaration:

// NSObjCRuntime.h
double NSFoundationVersionNumber;

It will export a JavaScript variable called NSFoundationVersionNumber:

console.log("iOS version: " + NSFoundationVersionNumber); // "Version: 1141.1", the version number will differ

Macros are not Available

There are limitations though. We do not have access to APIs that depend on the preprocessor. For example the following will NOT be exposed:

#define NSFoundationVersionNumber_iOS_6_1  993.00

The preprocessor will replace the occurrences of NSFoundationVersionNumber_iOS_6_1 with 993.00 in C but we do not have that information available in JavaScript. You will have to define variables with these constants on your own:

var NSFoundationVersionNumber_iOS_6_1 = 993.00;
if (NSFoundationVersionNumber >= NSFoundationVersionNumber_iOS_6_1) {
    // iOS 6.1 or up.
}

Enums Members

The members of enums are exposed as global variables in JavaScript similar to C variables.