# Io Reference

Core / Core / CFunction

|  | A container for a pointer to a C function binding. CFunction's can only be defined from the C side and act like blocks in that when placed in a slot, are called when the slot is activated. The for, if, while and clone methods of the Lobby are examples of CFunctions. CFunctions are useful for implementing methods that require the speed of C or binding to a C library.
|  | ==(anObject) Returns self if the argument is a CFunction with the same internal C function pointer. asSimpleString Returns the CFunction name. asString Same as asSimpleString. id Returns a number containing a unique id for the receiver's internal C function. name Returns the CFunction name in the form CFunction_Pointer.") performOn(target, blockLocals, optionalMessage, optionalContext) Activates the CFunctions with the supplied settings. typeName Returns the owning type of the CFunction or nil if the CFunction can be called on any object. uniqueName Returns the name given to the CFunction.