def next

mylsm-lsm-store@0.6.0.1 · src/scan/Cursor.bend:21

import Base

21# Returns at most one entry and retains the remaining source suffix.
22def next(cursor: Cursor) -> Step:
23  match cursor:
24    case CursorReady{entries}:
25      match entries:
26        case Nil{}: CursorEnd{CursorEnded{}}
27        case Con{entry, tail}: CursorItem{entry, CursorReady{tail}}
28    case CursorEnded{}: CursorEnd{CursorEnded{}}
29    case CursorClosed{}: CursorEnd{CursorClosed{}}
30    case CursorFailed{code, message}:
31      CursorError{CursorFailed{code, message}}