[SOLVED] Sed replace string on alphanumeric with certain length that must contain one capitalized letter and one number

Sed replace string on alphanumeric with certain length that must contain one capitalized letter and one number

I want to do a string replacement on any string that is surrounded by a word boundary that is alphanumeric and is 14 characters long. The string must contain at least one capitalized letter and one number. I know (I think I know) that I'll need to use positive look ahead for the capitalized letter and number. I am sure that I have the right regex pattern. What I don't understand is why sed is not matching. I have used online tools to validate the pattern like regexpal etc. Within those tools, I am matching the string like I expect.

Here is the regex and sed command I'm using.

\b(?=.*[A-Z])(?=.*[0-9])[a-zA-Z0-9]{14}\b

The sed command I'm testing with is

echo "asdfASDF1234ds" | sed 's/\b(?=.*[A-Z])(?=.*[0-9])[a-zA-Z0-9]{14}\b/NEW_STRING/g'

I would expect this to match on the echoed string.

Solution

sed doesn't support lookaheads, or many many many other modern regex Perlisms. The simple fix is to use Perl.

perl -pe 's/\b(?=.*[A-Z])(?=.*[0-9])[a-zA-Z0-9]{14}\b/NEW_STRING/g' <<< "asdfASDF1234ds"