+Each action will return a success flag. Actions can be chained such that
+the chain only continues when there are successes, or failures, or either.
+The `,` separator will always chain to the next action. The `|` separator
+will abort the chain if the action preceding it succeeds, and the `&` will
+abort the chain if the action preceding it fails. For example, in the default
+bindings, tab is bound as
+
+```
+"Tab": "Autocomplete|IndentSelection|InsertTab"
+```
+
+This means that if the `Autocomplete` action is successful, the chain will abort.
+Otherwise, it will try `IndentSelection`, and if that fails too, it will
+execute `InsertTab`.
+