LibraryFunctionDeclaration
LibraryFunctionDeclaration["extName",lib,type] represents a function declaration that exposes the library function extName with the type type from the library lib, for use in compiled code.
LibraryFunctionDeclaration[name->"extName",lib,type] aliases the function with name in compiled code.
LibraryFunctionDeclaration[nameSpec,type] assumes that the library will be loaded by the time the function is compiled.
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