Emacs正则表达式可搜索包含多个单词的行

Question

I am trying to understand whether regexp search can be used to search for lines that contain a certain word multiple times.

For example, I would like to find the line below because it contain twice the word Cable

<Connection Action="New" ID="277766368412" From="Cable:25425374" FromPosition="84" To="Cable:25389991" ToPosition="12"></Connection>

What should my regexp look like?

Thanks

Joe

Answer 1

You should clarify the question, because the way it is, the obvious "Cable.*Cable" works.

Maybe you want references, they work as well: "\\\\(Cable\\\\).*\\\\1" .

Just in case you didn't know before re-builder is a nice tool. Just paste your string into a buffer and experiment with re-builder .

Answer 2

Something like \\<\\(.*\\)\\>.*\\1 should work, although you might want to have a more restrictive pattern inside the capturing parenteses; the current one doesn't attempt to restrict the matched pattern to a single "word" but you could change the dot to eg [A-Za-z] if that's a suitable "word" definition for you.