Saw this idea referenced in a Relay ticket: facebook/relay#309 (comment)

Per offline discussion with @leebyron and @dschafer we'll probably have to add support for fragment aliases in the language to make this seamless. This would use your earlier proposal, @fson:

# Relay products
fragment on User {
  foo: ${Child.getFragment('foo')},
}
# Raw GraphQL
fragment on User {
  foo: ...sub_0 # name generated by `relay-babel-plugin`
}

Thought it might be useful to open a ticket here as a reminder or for more discussion.