EOL Special Char not matching

Posted by Aurélien Ribon on Stack Overflow See other posts from Stack Overflow or by Aurélien Ribon
Published on 2010-03-19T20:55:56Z Indexed on 2010/03/19 22:41 UTC
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Hello,

I am trying to find every "a -> b, c, d" pattern in an input string. The pattern I am using is the following :

"^[ \t]*(\\w+)[ \t]*->[ \t]*(\\w+)((?:,[ \t]*\\w+)*)$"

This pattern is a C# pattern, the "\t" refers to a tabulation (its a single escaped litteral, intepreted by the .NET String API), the "\w" refers to the well know regex litteral predefined class, double escaped to be interpreted as a "\w" by the .NET STring API, and then as a "WORD CLASS" by the .NET Regex API.

The input is :

a -> b
b -> c
c -> d

The function is :

private void ParseAndBuildGraph(String input) {
    MatchCollection mc = Regex.Matches(input, "^[ \t]*(\\w+)[ \t]*->[ \t]*(\\w+)((?:,[ \t]*\\w+)*)$", RegexOptions.Multiline);
    foreach (Match m in mc) {
        Debug.WriteLine(m.Value);
    }
}

The output is :

c -> d

Actually, there is a problem with the line ending "$" special char. If I insert a "\r" before "$", it works, but I thought "$" would match any line termination (with the Multiline option), especially a \r\n in a Windows environment. Is it not the case ?

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