#!/bin/bash
s=" hello
world
title: this is-the_test string with number 2, to-test CAMEL String
end! "
grep -o 'title:.*' <<< "$s" | cut -f2 -d: | sed -r 's/([^[:alnum:]]+)([0-9a-zA-Z])/\U\2/g' | tr -d ' '
sed -En '/.*title: *(.*[[:alnum:]]).*/{s//\1/;s/([^[:alnum:]]+|^)([0-9a-zA-Z])/\U\2/gp}' <<< "$s"
sed -En '/.*title: *(.*[[:alnum:]]).*/{s//\1/;s/([^[:alnum:]]+|^)([0-9a-zA-Z])/\U\2/gp}' \
<<< "title:this is, a test, , ,&"
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