From 93e668bad5b551fc839b142f74058e3b1fa01a32 Mon Sep 17 00:00:00 2001
From: Koichi Nakamura <koichi@idein.jp>
Date: Wed, 6 Jan 2021 17:23:29 +0900
Subject: [PATCH] Add [unless]

---
 bootstrap.fs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/bootstrap.fs b/bootstrap.fs
index 61a3f6c..392517f 100644
--- a/bootstrap.fs
+++ b/bootstrap.fs
@@ -1711,6 +1711,11 @@ switch-to-4th-stage
     then
 ; immediate
 
+: [unless] ( f -- )
+    not
+    [compile] [if]
+; immediate
+
 : [else]
     \ If the condition is false, [else] is skipped by [if].
     \ So when the execution reaches [else] it means that