From 35616c6eabc661a8d5be257a040a8effeb9e01f1 Mon Sep 17 00:00:00 2001
From: Ian Butterworth <i.r.butterworth@gmail.com>
Date: Sun, 29 Sep 2024 11:50:38 -0700
Subject: [PATCH 1/3] make UndefVarError aware of imported modules

---
 base/experimental.jl    |  2 +-
 stdlib/REPL/src/REPL.jl | 13 ++++++++++++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/base/experimental.jl b/base/experimental.jl
index 6e757e9fa0e5f..555d5e03d667a 100644
--- a/base/experimental.jl
+++ b/base/experimental.jl
@@ -321,7 +321,7 @@ function show_error_hints(io, ex, args...)
             @invokelatest handler(io, ex, args...)
         catch err
             tn = typeof(handler).name
-            @error "Hint-handler $handler for $(typeof(ex)) in $(tn.module) caused an error"
+            @error "Hint-handler $handler for $(typeof(ex)) in $(tn.module) caused an error" err
         end
     end
 end
diff --git a/stdlib/REPL/src/REPL.jl b/stdlib/REPL/src/REPL.jl
index 44fe0446240c6..8482e39538b64 100644
--- a/stdlib/REPL/src/REPL.jl
+++ b/stdlib/REPL/src/REPL.jl
@@ -74,7 +74,18 @@ end
 function _UndefVarError_warnfor(io::IO, m::Module, var::Symbol)
     Base.isbindingresolved(m, var) || return false
     (Base.isexported(m, var) || Base.ispublic(m, var)) || return false
-    print(io, "\nHint: a global variable of this name also exists in $m.")
+    active_mod = Base.active_module()
+    mod_imported = in(Symbol(m), names(active_mod, imported=true))
+    if !mod_imported && Symbol(m) == var
+        print(io, "\nHint: $m is loaded but not imported in the active module `$(active_mod)`.")
+    else
+        print(io, "\nHint: a global variable of this name also exists in $m")
+        if mod_imported
+            print(io, ".")
+        else
+            print(io, ", which is loaded but not imported in the active module `$(active_mod)`.")
+        end
+    end
     return true
 end
 

From d25c7f1b394e83b0efa9ec9090b153ed6856f0d5 Mon Sep 17 00:00:00 2001
From: Ian Butterworth <i.r.butterworth@gmail.com>
Date: Sun, 29 Sep 2024 15:33:58 -0700
Subject: [PATCH 2/3] use isdefined

---
 stdlib/REPL/src/REPL.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/stdlib/REPL/src/REPL.jl b/stdlib/REPL/src/REPL.jl
index 8482e39538b64..a2496bbb0d03d 100644
--- a/stdlib/REPL/src/REPL.jl
+++ b/stdlib/REPL/src/REPL.jl
@@ -75,7 +75,7 @@ function _UndefVarError_warnfor(io::IO, m::Module, var::Symbol)
     Base.isbindingresolved(m, var) || return false
     (Base.isexported(m, var) || Base.ispublic(m, var)) || return false
     active_mod = Base.active_module()
-    mod_imported = in(Symbol(m), names(active_mod, imported=true))
+    mod_imported = isdefined(active_mod, Symbol(m))
     if !mod_imported && Symbol(m) == var
         print(io, "\nHint: $m is loaded but not imported in the active module `$(active_mod)`.")
     else

From 0984e42b7daad9a63809e8b7e7879583a93ef11e Mon Sep 17 00:00:00 2001
From: Ian Butterworth <i.r.butterworth@gmail.com>
Date: Tue, 1 Oct 2024 11:49:15 -0400
Subject: [PATCH 3/3] suggestions

Co-Authored-By: Jameson Nash <vtjnash+github@gmail.com>
---
 base/experimental.jl    |  4 ++--
 stdlib/REPL/src/REPL.jl | 13 ++++++-------
 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/base/experimental.jl b/base/experimental.jl
index 555d5e03d667a..648b5da0ed9a1 100644
--- a/base/experimental.jl
+++ b/base/experimental.jl
@@ -319,9 +319,9 @@ function show_error_hints(io, ex, args...)
     for handler in hinters
         try
             @invokelatest handler(io, ex, args...)
-        catch err
+        catch
             tn = typeof(handler).name
-            @error "Hint-handler $handler for $(typeof(ex)) in $(tn.module) caused an error" err
+            @error "Hint-handler $handler for $(typeof(ex)) in $(tn.module) caused an error" exception=current_exceptions()
         end
     end
 end
diff --git a/stdlib/REPL/src/REPL.jl b/stdlib/REPL/src/REPL.jl
index a2496bbb0d03d..272b907165341 100644
--- a/stdlib/REPL/src/REPL.jl
+++ b/stdlib/REPL/src/REPL.jl
@@ -75,15 +75,14 @@ function _UndefVarError_warnfor(io::IO, m::Module, var::Symbol)
     Base.isbindingresolved(m, var) || return false
     (Base.isexported(m, var) || Base.ispublic(m, var)) || return false
     active_mod = Base.active_module()
-    mod_imported = isdefined(active_mod, Symbol(m))
-    if !mod_imported && Symbol(m) == var
-        print(io, "\nHint: $m is loaded but not imported in the active module `$(active_mod)`.")
+    print(io, "\nHint: ")
+    if isdefined(active_mod, Symbol(m))
+        print(io, "a global variable of this name also exists in $m.")
     else
-        print(io, "\nHint: a global variable of this name also exists in $m")
-        if mod_imported
-            print(io, ".")
+        if Symbol(m) == var
+            print(io, "$m is loaded but not imported in the active module $active_mod.")
         else
-            print(io, ", which is loaded but not imported in the active module `$(active_mod)`.")
+            print(io, "a global variable of this name may be made accessible by importing $m in the current active module $active_mod")
         end
     end
     return true