如何创建一个正则表达式，通过ruby的gsub替换字符串中的所有匹配项？

Question

I wonder why my regular expression will not work, I require to achieve the following behavior:

"aoaoaoaoaoao".gsub!(/o/, 'e')

The above will correctly give me: aeaeaeaeaeae

Now, The real thing looks like this:

"Today I ate a ((noun)), and it tasted ((adjective))".gsub!(/\(\(.*\)\)/, "word")

And its result is: "Today I ate a word" , But I had hoped It'd return to me: "Today I ate a word, and it tasted word"

It's obvious there's problem with my regular expression, (right?) because it'll only replace once. Could you guys please tell me how to make it replace all matches? (like in my first example)

Thank very much!

Answer 1

You need the following regex:

/\(\(.*?\)\)/

.*? consumes as little characters as possible to obtain a match. So the problem was not that the regex replaced once but that it matched too large a part of the string - from the first (( to the last )) .