length on seq

1 files changed, 6 insertions, 0 deletions

diff --git a/chunk.d b/chunk.d
index 70d7b1c..47d3c73 100644
--- a/chunk.d
+++ b/chunk.d
@@ -45,6 +45,7 @@ abstract class Seq {
     SeqType type;
     abstract Value first();
     abstract Seq rest();
+    abstract int length();
 }
 
 class List : Seq {
@@ -71,6 +72,10 @@ class List : Seq {
         return ret;
     }
 
+    override int length() {
+        return to!int(this.inner.length);
+    }
+
     override string toString() {
         return format("list ('%s' + %d)", printableValue(this.inner[0]), this.inner.length - 1);
     }
@@ -108,6 +113,7 @@ enum OpCode {
 
     OP_FIRST,   // No?
     OP_REST,
+    OP_LENGTH,
 
     OP_TYPE_CHECK_NUMBER,
     OP_TYPE_CHECK_BOOLEAN,