AMDG Salvatore Benedetto wrote:

On 5 May 2010 16:10, Nat Goodspeed wrote:

...

This might (or might not) work better: "\\.\\/\\w+(\\.txt)"

Indeed I was missing a backslash.

The following worked as I expected.

std::string expression("\.\/\\w+(\.txt)");

Actual not. The first level of backslashes is processed by C++. The regex library never sees them. This pattern with match x/filename-txt, since . is a wild card. In Christ, Steven Watanabe

Actual not. The first level of backslashes is processed by C++. The regex library never sees them. This pattern with match x/filename-txt, since . is a wild card.

Oh so it's just a case that it matches string "./File.txt".

So basically I have to double backslash everytime?

Everytime you want the regex engine to see a "\" you have to put "\\" in your string since the first \ gets swallowed by the C++ parser and doesn't appear in the actual string placed in your program (of course if the regular expressions were read in from an extern text file or something then this wouldn't be the case). HTH, John.

Le 05/05/2010 17:20, Mathias Gaunard a écrit :

Salvatore Benedetto wrote:

...

So basically I have to double backslash everytime?

If you want that backslash to make it to the regex engine, yes.

Otherwise, you may use raw string literals if your compiler supports them. GCC 4.5 is supposed to support it, but it appears completely broken.

My bad, I had a wrong build, raw string literals appear to work in 4.5