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.net - "Using The Iteration Variable In A Lambda Expression May Have Unexpected Results"

Edit: Here is a much more simpler example of this issue (i've deleted my original question):

Dim numbers1 As New List(Of Int32)({1, 2, 3})
Dim numbers2 As New List(Of Int32)({3, 4, 5})
For Each n1 In numbers1
' no warning '
Dim contains = numbers2.Contains(n1)


The local variable number1 is redundant and makes the code less readable as @Meta-Knight already has emphasized. Note: All three ways are safe and give the correct result.

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Get: "iteration Variable In A Lambda Expression May Have Unexpected Results"
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