I've spent a little bit of time locally trying to figure out what's going on.
In short, after adding the repository 'ppa:ondrej/php' I should be able to apt-get install php7.1 but instead I get the following:
E: Unable to locate package php7.1
E: Couldn't find any package by glob 'php7.1'
E: Couldn't find any package by regex 'php7.1'
I've spent a little bit of time locally trying to figure out what's going on.
In short, after adding the repository 'ppa:ondrej/php' I should be able to
apt-get install php7.1but instead I get the following: