Class LexerTransformer

A transform stream that converts a stream of tokens into a stream of rows.

Example: Parse a CSV with headers by data

new ReadableStream({
  start(controller) {
    controller.enqueue("name,age\r\n");
    controller.enqueue("Alice,20\r\n");
    controller.close();
  }
})
  .pipeThrough(new LexerTransformer())
  .pipeTo(new WritableStream({ write(tokens) {
    for (const token of tokens) {
      console.log(token);
    }
  }}));
// { type: Field, value: "name", location: {...} }
// { type: FieldDelimiter, value: ",", location: {...} }
// { type: Field, value: "age", location: {...} }
// { type: RecordDelimiter, value: "\r\n", location: {...} }
// { type: Field, value: "Alice", location: {...} }
// { type: FieldDelimiter, value: ",", location: {...} }
// { type: Field, value: "20" }
// { type: RecordDelimiter, value: "\r\n", location: {...} }
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