Platform is Centos 7
I'm working towards extracting the non-version portion of a filename and puzzled by this result:
echo "xorg-x11-font-utils-7.5-21.el7.x86_64.rpm" | sed -nr "s/([[:alpha:]]+)-[0-9].*\.*rpm/\1/p"
which yields
xorg-x11-font-utils
hence [:alpha:]+ appears to match a string including two *1*s, two non-alpha characters. I was expecting this not to match at all.
Explanations?