sentences:  A typical use of codice_1/codice_2 is implementation of an exception mechanism that exploits the ability of codice_2 to reestablish program or thread state, even across multiple levels of function calls.A less common use of codice_1 is to create syntax similar to coroutines.codice_1 saves the current environment (the program state), at some point of program execution, into a platform-specific data structure (codice_8) that can be used at some later point of program execution by codice_2 to restore the program state to that saved by codice_1 into codice_8.