Add a signal at start of run (mesa#3284)

quaquel · web-flow · commit 86e71ed0c286 · 2026-02-12T17:50:43.000+01:00
diff --git a/mesa/model.py b/mesa/model.py
@@ -119,7 +119,8 @@ def __init__(
         super().__init__(*args, **kwargs)
         self.running: bool = True
         self.steps: int = 0
-        self.time: float = 0.0
+        self._time = 0.0
+        # self.time: float = 0.0
         self.agent_id_counter: int = 1
 
         # Track if a simulator is controlling time
@@ -210,6 +211,9 @@ def _advance_time(self, until: float) -> None:
             until: The time to advance to
 
         """
+        if self._time == 0.0:
+            self.time = 0.0  # this emits ObservableSignal.CHANGED
+
         while True:
             try:
                 event = self._event_list.pop_event()
