Regular expression to match single bracket pairs but not double bracket pairs

Question

Is it possible to make a regular expression to match everything within single brackets but ignore double brackets, so for example in:

{foo} {bar} {{baz}}
         


        

Answer 1

In many languages you can use lookaround assertions:

(?

Explanation:

• (?: previous character is not a {
• \{([^}]+)\}: something inside curly braces, e.g. {foo}
• (?!\}): following character is not a }