Function: unknownEscapeSequence()

unknownEscapeSequence(position, body): Hl7ParseWarning

Build an UNKNOWN_ESCAPE_SEQUENCE warning for a terminated escape sequence (\..\) whose body is not a recognized HL7 escape. The message NEVER embeds the escape body: only its length and, when the body's first character is a recognized HL7 escape-identifier letter (structural HL7 grammar, not PHI: e.g. Z for a vendor escape, . for a formatting escape), that single letter. A body that doesn't start with a known escape letter is untrusted field text and names no character at all. The sequence itself is still preserved verbatim in the parsed output: only the WARNING message is PHI-safe.

Parameters

position

Hl7Position

body

string

Returns

Hl7ParseWarning

Example

import { unknownEscapeSequence } from "@cosyte/hl7";
const w = unknownEscapeSequence({ segmentIndex: 2, fieldIndex: 3 }, "Z99");
// message: `Unknown HL7 escape sequence of type "Z" (3 chars) preserved verbatim.`