SE_FUNCTION_GLOBALSE_FUNCTION_TEXT
This is a special member that cannot be created, written to, or deleted. Only script functions have this member, for all other objects SE_FUNCTION_TEXT is undefined. The value associated with the member is a text version of the script function's body.
Some builds, such as when JSE_SAVE_FUNCTION_TEXT is not defined (the default if JSE_MIN_MEMORY is defined), do not save the information necessary to rebuild the function's text representation and therefore will always return an undefined value.