# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression.
sed -E 's/(^nvsm)(\-)(apis|dshm|cli)(\-|\_)(\d{2}|\(\d{2}\))(\.)(0?[1-9]|1[012])(\.|\-)(\d{1}|\d{2})(\-|\_|\.)(\d{1}|\d{2}|all|el\d{1})(\.)(el\d{1}|(deb)|(noarch))(|(\.)((x86_64)|(rpm))(\.)(rpm))$/$1/gim;t' <<< "nvsm-dshm-18.12-2.el7.noarch.rpm"
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html