A support similar to Java iteration could be exposed by CLI. By leveraging the variable and the control flow CLI features, a command can be exposed to iterate collections and execute CLI commands/operations for each item present in the collection.
Something like:
for varName in :read-children-names(type=deployment)
echo Manifest file in $varName
attachment display --operation=/deployment=$varName:read-content(path=META-INF/MANIFEST.MF)
done