Imports System
Imports System.Text.RegularExpressions
 
Module Test
	Sub Main()
		Dim regex As New Regex("(?<=^[^:]*;\s*)[^\s:](?=[^:]*(?:$|:))", RegexOptions.Multiline)
		Dim input As String =
			"[Foo][Bar]Foo bar foo bar: foo; bar: foo bar foo bar __" & vbCrlf &
			"[Foo][Bar]Foo; bar: foo bar __ foo bar foo bar" & vbCrlf &
			"[Foo]Foo bar foo bar foo bar: foo __ bar; foo bar __ foo bar" & vbCrlf &
			"[Bar]Foo; bar; foo"
 
		Console.WriteLine(regex)
		Console.WriteLine(regex.Replace(input, AddressOf ConvertToUppercase))
	End Sub
 
	Function ConvertToUppercase(match As Match) As String
		Return match.Groups(0).Value.ToUpper()
	End Function
End Module

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