Question

This may sound like a silly question but in D (using std.regex) how do you match a literal dot in a string?

Using this code i’m checking for the file extension .bmp so i perform a simple regex match on it. If i try and escape the dot like this i get an error.

Regex!char Pattern = regex("\.bmp$", "i");

if (match(FileName, Pattern).empty)
{
    FileName ~= ".bmp";
}

Error: Undefined escape sequence \.

Even in the documentation it doesn’t mention matching dots.

Any ideas?

Answer 1

I guess you need to double escape it (You want \. in the regex). In your current code, you are single escaping it, so D tries to interpret it as something for itself, not for regex. Double escaping tells D that you want a literal \ in the string.

So in the end, it should look like "\\.bmp$".