append method

  1. @override
void append(
  1. String name,
  2. String value
)

Appends a new value onto an existing header inside a Headers object, or adds the header if it does not already exist.

MDN Reference

Implementation

@override
void append(String name, String value) {
  if (name.toLowerCase() == 'traceparent') {
    return _headers.set(name, value);
  }

  _headers.append(name, value);
}