subplot.md: Document scenario language a bit more

Signed-off-by: Daniel Silverstone <dsilvers@digital-scurf.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/subplot.py b/subplot.py
index 40678c2..e083ebd 100644
--- a/subplot.py
+++ b/subplot.py
@@ -128,3 +128,7 @@ def file_ends_in_two_newlines(ctx, filename=None):
 def binary(basename):
     srcdir = globals()["srcdir"]
     return os.path.join(srcdir, "target", "debug", basename)
+
+
+def do_nothing(ctx):
+    pass