+ / 9. C<<1 setjmp()/longjmp() based exceptions, updated 2008-09-30
+ '----------------------------------------------------------------------- */
+#define FAILED_TO_FAIL -273
+#define SYSTEM_FAILURE -1
+#define LOCAL_FAILURE 13
+#define LIBRARY_FAILURE 23
+#define EVIL_FAILURE 666
+#define try _NEW(E,0) if(!(_E=setjmp(_EENV)))
+#define fail(E) longjmp(_EENV,((E)>0?(E):FAILED_TO_FAIL))
+#define pass_failure (_Eatom->__next?longjmp((pop(_Eatom,_Estack),_EENV),_E):_SYSFAIL(FAILED_TO_FAIL))
+#define else_switch_failures else switch(_E)
+#define else_catch(E) else if (_E==(E))
+/* .----------------------------------------------------------------------.
+ / 10. implementation of C<<1 library functions, updated 2008-01-26 xCh.