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Boolean values

FFI supports boolean values, represented as JavaScript booleans (true or false). The native code representation of a boolean value isn't actually strictly defined, but it is probably safe to assume that if your native library is written in a language with booleans in it (eg. C, C++, Rust) then the FFI boolean value will match the library.

Fast API support

V8's Fast API calls support booleans as both parameters and return values.