delete_rules library Null safety

Classes

CatchAllDeleteRule
Fallback rule for delete operations which simply deletes specified text range without any special handling.
DeleteRule
A heuristic rule for delete operations.
EnsureEmbedLineRule
Prevents user from merging line containing an embed with other lines.
PreserveLineStyleOnMergeRule
Preserves line format when user deletes the line's line-break character effectively merging it with the next line.