iris

commit 07c4f4c7c10d9fab9f86a93096ebea0ab29b8ec8
parent 6c977b947bfd7986d1f0daf541bcd40abc949b91
Author: sin <sin@2f30.org>
Date:   Thu, 15 May 2014 12:29:40 +0100

Implement set

Diffstat:
M
parser.c
 | 
31
+++++++++++++++++++++++++++++++

1 file changed, 31 insertions(+), 0 deletions(-)
diff --git a/parser.c b/parser.c
@@ -62,6 +62,7 @@ struct object {
 static struct object *evaldefine(struct object *);
 static struct object *evalok(struct object *);
 static struct object *evalquote(struct object *);
+static struct object *evalset(struct object *);
 
 struct {
 	char *name;
@@ -71,6 +72,7 @@ struct {
 	{ .name = "define", .fn = evaldefine },
 	{ .name = "ok",     .fn = evalok     },
 	{ .name = "quote",  .fn = evalquote  },
+	{ .name = "set",    .fn = evalset    },
 };
 
 static int
@@ -341,6 +343,35 @@ evalquote(struct object *o)
 	return NULL;
 }
 
+static struct object *
+evalset(struct object *o)
+{
+	struct object *ocar;
+	struct object *var, *val;
+
+	if (o->type == OPair) {
+		ocar = car(o);
+		if (ocar->type == OIdentifier &&
+		    strcmp(ocar->d.i.s, "set") == 0) {
+			var = cadr(o);
+			if (var->type != OIdentifier)
+				return error("expected identifier");
+			if (!lookupsym(var->d.i.s))
+				return error("unbound identifier");
+			if (!caddr(o))
+				return error("expected sexpression");
+			if (cadddr(o))
+				return error("multiple arguments to set");
+			val = eval(caddr(o));
+			if (val->type == OError)
+				return val;
+			addsym(var->d.i.s, val);
+			return lookupsym("ok");
+		}
+	}
+	return NULL;
+}
+
 struct object *
 eval(struct object *o)
 {