Add target run check

*   Add `has_run` check to targets to ensure targets only execute once per
    build

1 files changed, 5 insertions, 2 deletions

diff --git a/xnt/__init__.py b/xnt/__init__.py
index 61de895..767c2b7 100644
--- a/xnt/__init__.py
+++ b/xnt/__init__.py
@@ -60,10 +60,13 @@ def target(target_fn):
        build file as a "target" method, or a method meant
        to be invoked from Xnt
     """
+    has_run = [False,]
     def wrap():
         """Inner wrapper function for decorator"""
-        print(target_fn.__name__ + ":")
-        return target_fn()
+        if not has_run[0]:
+            has_run[0] = True
+            print(target_fn.__name__ + ":")
+            return target_fn()
     wrap.decorator = "target"
     wrap.__doc__ = target_fn.__doc__
     return wrap