Switched to using st.session_state to manage state.

app.py

@@ -19,18 +19,21 @@ st.markdown("***")
 # https://discuss.streamlit.io/t/simple-example-of-persistence-and-waiting-for-input/2111
 @st.cache(allow_output_mutation=True)
 def Edits():
-    return pd.DataFrame([], columns=["Edit input", "Edit label"])
+    return 
 
 @st.cache(allow_output_mutation=True)
 def ModelOutput():
-    return pd.DataFrame([], columns=["Input", "Generation", "Edits applied"])
+    return 
 
-edits = Edits()
-model_outputs = ModelOutput()
+if "init" not in st.session_state:
+    # Perform first-time initialization
+    st.session_state.edits = pd.DataFrame([], columns=["Edit input", "Edit label"])
+    st.session_state.model_outputs = pd.DataFrame([], columns=["Input", "Generation", "Edits applied"])
+    st.session_state.init = True
 
 def reset():
-    edits.drop(edits.index, inplace=True)
-    model_outputs.drop(edits.index, inplace=True)
+    st.session_state.edits.drop(st.session_state.edits.index, inplace=True)
+    st.session_state.model_outputs.drop(st.session_state.edits.index, inplace=True)
 
     selected_alg = st.session_state.alg_selector
     selected_alg_idx = EDIT_ALGS.index(selected_alg)
@@ -38,10 +41,10 @@ def reset():
     ############# Need to reset the model here (and maybe show progress spinner?)
 
 def apply_edit():
-    edits.loc[len(edits)] = [str(edit_input), str(edit_label)]
+    st.session_state.edits.loc[len(st.session_state.edits)] = [str(edit_input), str(edit_label)]
 
 def sample_model():
-    model_outputs.loc[len(model_outputs)] = [str(test_input), "blah blah blah", len(edits)]
+    st.session_state.model_outputs.loc[len(st.session_state.model_outputs)] = [str(test_input), "blah blah blah", len(st.session_state.edits)]
 
 col1, col2 = st.columns([5,1])
 with col1:
@@ -51,7 +54,7 @@ with col2:
     st.button("Clear edits", on_click=reset)
 
 st.write("Edits applied so far:")
-st.table(edits)
+st.table(st.session_state.edits)
 
 st.markdown("***")
 
@@ -66,7 +69,7 @@ with col3:
 
 st.markdown("***")
 
-if len(edits) == 0:
+if len(st.session_state.edits) == 0:
     title = "Input to sample from *unedited* model:"
 else:
     title = f"Input to sample from *edited* model:"
@@ -78,4 +81,4 @@ with col2:
     generate_button = st.button("Generate", on_click=sample_model)
 
 st.write("Model generation history:")
-st.table(model_outputs)
+st.table(st.session_state.model_outputs)