explainshell.com - sed.1posix -i -e ‘s/class/enum/’ ./billing-method.ts

-i -e ?s/class/enum/? ./billing-method.ts

stream editor

-e  script
       Add  the  editing  commands  specified  by  the script option-argument to the end of the script of
       editing commands. The script option-argument shall have the same properties as the script operand,
       described in the OPERANDS section.