wip literal per ANS forth

forth/core.zf

@@ -58,6 +58,8 @@
 : allot  h +!  ;
 : var : ' lit , here 5 allot here swap ! 5 allot postpone ; ;
 : const : ' lit , , postpone ; ;
+: constant >r : r> postpone literal postpone ; ;
+: variable >r here r> postpone , constant ;
 
 ( 'begin' gets the current address, a jump or conditional jump back is generated
   by 'again', 'until' )

src/zforth/zforth.c

@@ -49,6 +49,7 @@ typedef enum {
 	PRIM_JMP,     PRIM_JMP0,      PRIM_TICK, PRIM_COMMENT, PRIM_PUSHR,    PRIM_POPR,
 	PRIM_EQUAL,   PRIM_SYS,       PRIM_PICK, PRIM_COMMA,   PRIM_KEY,      PRIM_LITS,
 	PRIM_LEN,     PRIM_AND,       PRIM_OR,   PRIM_XOR,     PRIM_SHL,      PRIM_SHR,
+	PRIM_LITERAL,
 	PRIM_COUNT
 } zf_prim;
 
@@ -58,7 +59,8 @@ static const char prim_names[] =
 	_("pickr")   _("_immediate") _("@@")    _("!!")    _("swap")      _("rot")
 	_("jmp")     _("jmp0")       _("'")     _("_(")    _(">r")        _("r>")
 	_("=")       _("sys")        _("pick")  _(",,")    _("key")       _("lits")
-	_("##")      _("&")          _("|")     _("^")     _("<<")        _(">>");
+	_("##")      _("&")          _("|")     _("^")     _("<<")        _(">>")
+	_("_literal");
 
 
 /* User variables are variables which are shared between forth and C. From
@@ -552,6 +554,14 @@ static void do_prim(zf_ctx *ctx, zf_prim op, const char *input)
 			COMPILING(ctx) = 0;
 			break;
 
+		case PRIM_LITERAL:
+			/* At compile time, compiles a value from the stack into the
+			 * definition as a literal. At run time, the value will be pushed
+			 * on the stack. */
+			if(COMPILING(ctx)) dict_add_lit(ctx, zf_pop(ctx));
+			/* FIXME: else abort "!compiling"? */
+			break;
+
 		case PRIM_LIT:
 			/* At run time, push next value from dictionary on stack */
 			ctx->ip += dict_get_cell(ctx, ctx->ip, &d1);