I have input strings which contain text in which some characters are in UTF-16 format and escaped with '\u'. I am trying to convert all the strings to UTF-8. For example, the string 'Alice & Bob & Carol' might be formatted in the input as:

'Alice \u0026 Bob \u0026 Carol'

To do my desired conversion, I was doing...:

$str =~ s/\\u([A-Fa-f0-9]{4})/pack("U", hex($1))/eg;

...which worked fine until I got to input strings that contained UTF-16 surrogate pairs like:

'Alice \ud83d\ude06 Bob'

How do I modify the above code that uses pack to work with UTF-16 surrogate pairs? I would really like a solution that just uses pack without having to use any additional libraries (JSON::XS, Encode, etc.).

In reply to How to Use Pack to Convert UTF-16 Surrogate Pairs to UTF-8? by WingedKnight

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