Add a suggestion to use the 'force' function in the 'uninitialised el…

…ement' error message (#231) Compaction of an immutable vector may crash with the confusing 'uninitialised element' error message (#220). The workaround is to use the 'force' function.
haskell · Jan 16, 2020 · fd35bac · fd35bac
1 parent c8d2d94
commit fd35bac
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/Data/Vector/Mutable.hs b/Data/Vector/Mutable.hs
@@ -193,7 +193,7 @@ loopM !n k = let
   in go 0
 
 uninitialised :: a
-uninitialised = error "Data.Vector.Mutable: uninitialised element"
+uninitialised = error "Data.Vector.Mutable: uninitialised element. If you are trying to compact a vector, use the 'force' function to remove uninitialised elements from the underlying array."
 
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