GH-21 Make the internal _quit the only QUIT.

src/post4.c

@@ -1343,7 +1343,7 @@ p4Repl(P4_Ctx *ctx, int rc)
 #define w_semi		words[1]
 		P4_WORD("_abort",	&&_abort,	0, 0x00),
 #define w_abort		words[2]
-		P4_WORD("_quit",	&&_quit,	0, 0x00),
+		P4_WORD("QUIT",		&&_quit,	0, 0x00),
 #define w_quit		words[3]
 		P4_WORD("_interpret",	&&_interpret,	0, 0x00),
 #define w_interpret	words[4]
@@ -1644,6 +1644,7 @@ _quit:		P4_RESET(ctx->rs);
 		/* Discard the current input buffer. */
 		ctx->input.offset = ctx->input.length = 0;
 		ctx->state = P4_STATE_INTERPRET;
+		ctx->frame = 0;
 		/*@fallthrough@*/
 	case P4_THROW_OK:
 		;

src/post4.p4

@@ -650,16 +650,6 @@ DEFER _fsp!
 \ ( i*x -- ⊥ )(F: k*x -- ⊥ )( R: j*x -- ⊥ )
 : ABORT -1 THROW ;
 
-\ GH-18
-\ QUIT resumes the REPL and never returns to the caller.
-\ Need to be sure to reset the catch_frame for future
-\ THROW CATCH ABORT or QUIT.
-\
-\ printf "' quit catch \n abort" | ./post4 ; echo $?
-\
-\ ( i*x -- ⊥ )(F: k*x -- ⊥ )
-: QUIT 0 catch_frame ! _quit ;
-
 \ ( xt -- )
 : execute-compiling
 	STATE @ IF EXECUTE EXIT THEN