--- a/lwasm/lwasm.c	Thu Apr 01 20:56:19 2010 -0600
+++ b/lwasm/lwasm.c	Tue Apr 06 21:03:19 2010 -0600
@@ -33,8 +33,53 @@
 
 #include "lwasm.h"
 
+void lwasm_register_error(asmstate_t *as, line_t *l, const char *msg, ...);
+
 lw_expr_t lwasm_evaluate_var(char *var, void *priv)
 {
+	asmstate_t *as = (asmstate_t *)priv;
+	lw_expr_t e;
+	importlist_t *im;
+	struct symtabe *s;
+	
+	s = lookup_symbol(as, as -> cl, var);
+	if (s)
+	{
+		e = lw_expr_build(lw_expr_type_special, lwasm_expr_syment, s);
+		return e;
+	}
+	
+	// undefined here is undefied unless output is object
+	if (as -> output_format != OUTPUT_OBJ)
+		goto nomatch;
+	
+	// check for import
+	for (im = as -> importlist; im; im = im -> next)
+	{
+		if (!strcmp(im -> symbol, var))
+			break;
+	}
+	
+	// check for "undefined" to import automatically
+	if (!im && CURPRAGMA(as -> cl, PRAGMA_UNDEFEXTERN))
+	{
+		im = lw_alloc(sizeof(importlist_t));
+		im -> symbol = lw_strdup(var);
+		im -> next = as -> importlist;
+		as -> importlist = im;
+	}
+	
+	if (!im)
+		goto nomatch;
+
+	e = lw_expr_build(lw_expr_type_special, lwasm_expr_import, im);
+	return e;
+
+nomatch:
+	if (as -> badsymerr)
+	{
+		lwasm_register_error(as, as -> cl, "Undefined symbol %s", var);
+	}
 	return NULL;
 }
 
@@ -59,6 +104,26 @@
 			else
 				return NULL;
 		}
+	
+	case lwasm_expr_syment:
+		{
+			return NULL;
+		}
+	
+	case lwasm_expr_import:
+		{
+			return NULL;
+		}
+	
+	case lwasm_expr_nextbp:
+		{
+			return NULL;
+		}
+	
+	case lwasm_expr_prevbp:
+		{
+			return NULL;
+		}
 	}
 	return NULL;
 }
@@ -482,6 +547,11 @@
 	return e;
 }
 
+int lwasm_reduce_expr(asmstate_t *as, lw_expr_t expr)
+{
+	lw_expr_simplify(expr, as);
+}
+
 void lwasm_save_expr(line_t *cl, int id, lw_expr_t expr)
 {
 	struct line_expr_s *e;
@@ -612,3 +682,8 @@
 		(*p) += 3;
 	return rval;
 }
+
+void lwasm_show_errors(asmstate_t *as)
+{
+	fprintf(stderr, "Errors encountered. FIXME - print out errors.\n");
+}