`GraphQLList`: Can it handle append/preprend/delete?

Can ordinary, flat lists be safely updated in mutations (e.g. adding, removing, updating an item?)

Does the relay specification define this?

[Mutations API](https://relay.dev/docs/v1.5.0/mutations/#range_delete) have access to [`RANGE_ADD`](https://relay.dev/docs/v1.5.0/mutations/#range_add) ([`@appendEdge`](https://relay.dev/docs/guided-tour/updating-data/graphql-mutations/#order-of-execution-of-updater-functions)?), [`RANGE_DELETE`](https://relay.dev/docs/v1.5.0/mutations/#range_delete) ([`@deleteRecord`](https://relay.dev/docs/guided-tour/updating-data/graphql-mutations/#order-of-execution-of-updater-functions)?)

Suppose `GraphQLList` don't work with those above features, is there any in the existing mutation specification to simulate adding, deleting, updating a single item?

How close can you get to connection-like behavior without needing to use a structure shaped like `edges.node`?

History: Unsettled issue from relay classic: https://github.com/facebook/relay/issues/444, https://github.com/facebook/relay/pull/1292

Start with the Relay v1.5.0 mutation documentation linked in the issue, especially RANGE_ADD/RANGE_DELETE and @appendEdge/@deleteRecord, then compare the earlier Relay issue #444 and pull request #1292. Done would be a documented, settled answer or an explicitly scoped implementation path for updating flat GraphQLList values without connection-shaped data.

Written by the indexing model from the issue text.