From 1902f3593bb8cf3c4ab1be82e89a22f6d87d3c4f Mon Sep 17 00:00:00 2001
From: MarcoGorelli <33491632+MarcoGorelli@users.noreply.github.com>
Date: Mon, 29 Jan 2024 10:30:21 +0000
Subject: [PATCH] feat(python): raise more informative error message if someone
 lands on Expr.__bool__

---
 py-polars/polars/expr/expr.py | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/py-polars/polars/expr/expr.py b/py-polars/polars/expr/expr.py
index de83d8da4da7..43468daa2f5b 100644
--- a/py-polars/polars/expr/expr.py
+++ b/py-polars/polars/expr/expr.py
@@ -143,8 +143,13 @@ def __str__(self) -> str:
     def __bool__(self) -> NoReturn:
         msg = (
             "the truth value of an Expr is ambiguous"
-            "\n\nHint: use '&' or '|' to logically combine Expr, not 'and'/'or', and"
-            " use `x.is_in([y,z])` instead of `x in [y,z]` to check membership."
+            "\n\n"
+            "You probably got here by using a Python standard library function instead "
+            "of the native expressions API.\n"
+            "Here are some things you might want to try:\n"
+            "- instead of `pl.col('a') and pl.col('b')`, use `pl.col('a') & pl.col('b')`\n"
+            "- instead of `pl.col('a') in [y, z]`, use `pl.col('a').is_in([y, z])`\n"
+            "- instead of `max(pl.col('a'), pl.col('b'))`, use `pl.max_horizontal(pl.col('a'), pl.col('b'))`\n"
         )
         raise TypeError(msg)