Revert "remove unused clear_results"

This reverts commit 4a5e48b7bb.

streamlit_agent/clear_results.py

@@ -0,0 +1,32 @@
+import streamlit as st
+
+
+# A hack to "clear" the previous result when submitting a new prompt. This avoids
+# the "previous run's text is grayed-out but visible during rerun" Streamlit behavior.
+class DirtyState:
+    NOT_DIRTY = "NOT_DIRTY"
+    DIRTY = "DIRTY"
+    UNHANDLED_SUBMIT = "UNHANDLED_SUBMIT"
+
+
+def get_dirty_state() -> str:
+    return st.session_state.get("dirty_state", DirtyState.NOT_DIRTY)
+
+
+def set_dirty_state(state: str) -> None:
+    st.session_state["dirty_state"] = state
+
+
+def with_clear_container(submit_clicked: bool) -> bool:
+    if get_dirty_state() == DirtyState.DIRTY:
+        if submit_clicked:
+            set_dirty_state(DirtyState.UNHANDLED_SUBMIT)
+            st.experimental_rerun()
+        else:
+            set_dirty_state(DirtyState.NOT_DIRTY)
+
+    if submit_clicked or get_dirty_state() == DirtyState.UNHANDLED_SUBMIT:
+        set_dirty_state(DirtyState.DIRTY)
+        return True
+
+    return False

streamlit_agent/mrkl_demo.py

@@ -14,6 +14,7 @@ from langchain.callbacks import StreamlitCallbackHandler
 from langchain.utilities import DuckDuckGoSearchAPIWrapper
 
 from streamlit_agent.callbacks.capturing_callback_handler import playback_callbacks
+from streamlit_agent.clear_results import with_clear_container
 
 DB_PATH = (Path(__file__).parent / "Chinook.db").absolute()
 
@@ -24,9 +25,7 @@ SAVED_SESSIONS = {
     "are in the FooBar database?": "alanis.pickle",
 }
 
-st.set_page_config(
-    page_title="MRKL", page_icon="🦜", layout="wide", initial_sidebar_state="collapsed"
-)
+st.set_page_config(page_title="MRKL", page_icon="🦜", layout="wide", initial_sidebar_state="collapsed")
 
 "# 🦜🔗 MRKL"
 
@@ -102,10 +101,7 @@ if st.session_state["dirty_state"] == "dirty":
         st.empty()
     st.experimental_rerun()
 
-if (
-    not st.session_state["latest_user_input_executed"]
-    and st.session_state["dirty_state"] == "initial"
-):
+if not st.session_state["latest_user_input_executed"] and st.session_state["dirty_state"] == "initial":
     if st.session_state["latest_user_input"]:
         st.chat_message("user").write(st.session_state["latest_user_input"])
 
@@ -122,9 +118,7 @@ if (
                 [st_callback], str(session_path), max_pause_time=3
             )
         else:
-            answer = mrkl.run(
-                st.session_state["latest_user_input"], callbacks=[st_callback]
-            )
+            answer = mrkl.run(st.session_state["latest_user_input"], callbacks=[st_callback])
 
         result_container.write(answer)
         st.session_state["dirty_state"] = "dirty"