To further expand on poj's response, this is a case of calling context. You called the match (and capture) in scalar context, so the pattern match returned the number of matches (which would be at most 1, since you didn't use the g modifier on your RE). poj's addition of the parenthesis around the variable assignment changes the context to 'array context'. The results of a capture in scalar context return the number of matches, and in array context return the matches themselves.