bufferHelper("no newlines at all", "no newlines at all");
    bufferHelper("two lines\nbut no newline at end", "two lines\n", "but no newline at end");
    bufferHelper(
        "\nempty first line\nno newline at end", "\n", "empty first line\n", "no newline at end");
    bufferHelper("three\rlines\rno newline at end", "three\r", "lines\r", "no newline at end");

    bufferHelper("no newlines at all", "no newlines at all");
    bufferHelper("two lines\nbut no newline at end", "two lines\n", "but no newline at end");
    bufferHelper(
        "\nempty first line\nno newline at end", "\n", "empty first line\n", "no newline at end");
    bufferHelper("three\rlines\rno newline at end", "three\r", "lines\r", "no newline at end");

import (
	"iter"
	"unicode"
	"unicode/utf8"
)

// Lines returns an iterator over the newline-terminated lines in the byte slice s.
// The lines yielded by the iterator include their terminating newlines.
// If s is empty, the iterator yields no lines at all.
// If s does not end in a newline, the final yielded line will not end in a newline.
// It returns a single-use iterator.
func Lines(s []byte) iter.Seq[[]byte] {

  private static final ImmutableMap<Character, String> NO_REPLACEMENTS = ImmutableMap.of();
  private static final ImmutableMap<Character, String> SIMPLE_REPLACEMENTS =
      ImmutableMap.of(
          '\n', "<newline>",
          '\t', "<tab>",
          '&', "<and>");

  public void testSafeRange() throws IOException {
    // Basic escaping of unsafe chars (wrap them in {,}'s)
    CharEscaper wrappingEscaper =

		// Test some weird characters over the wire.
		{"foo", "newline\n", testData, false, true},
		{"foo", "newline\t", testData, false, true},
		{"foo", "newline \n", testData, false, true},
		{"foo", "newline$$$\n", testData, false, true},
		{"foo", "newline%%%\n", testData, false, true},
		{"foo", "newline \t % $ & * ^ # @ \n", testData, false, true},
		{"foo", "\n\tnewline \t % $ & * ^ # @ \n", testData, false, true},
	}

				acceptArg = false
			default:
				in.Error("bad definition for macro:", name)
			}
		}
	}
	var tokens []Token
	// Scan to newline. Backslashes escape newlines.
	for tok != '\n' {
		if tok == scanner.EOF {
			in.Error("missing newline in definition for macro:", name)
		}
		if tok == '\\' {
			tok = in.Stack.Next()
			if tok != '\n' && tok != '\\' {

The [bytes] package adds several functions that work with iterators:
- [Lines] returns an iterator over the
  newline-terminated lines in the byte slice s.
- [SplitSeq] returns an iterator over
  all substrings of s separated by sep.
- [SplitAfterSeq] returns an iterator
  over substrings of s split after each instance of sep.
- [FieldsSeq] returns an iterator over
  substrings of s split around runs of whitespace characters,
  as defined by unicode.IsSpace.

      with(sink) {
        writeInt(totalRuleBytes)
        for (domain in sortedRules) {
          write(domain).writeByte(NEWLINE)
        }
        writeInt(totalExceptionRuleBytes)
        for (domain in sortedExceptionRules) {
          write(domain).writeByte(NEWLINE)
        }
      }
    }
  }

  private suspend fun writeOutputFile(importResults: ImportResults) =

    @Nonnull
    default MessageBuilder a(Object value) {
        return append(String.valueOf(value));
    }

    /**
     * Append newline to the message buffer.
     *
     * @return the current builder
     */
    @Nonnull
    default MessageBuilder newline() {
        return append(System.lineSeparator());
    }

    /**
     * Append formatted content to the buffer.

The [strings] package adds several functions that work with iterators:
- [Lines] returns an iterator over
  the newline-terminated lines in the string s.
- [SplitSeq] returns an iterator over
  all substrings of s separated by sep.
- [SplitAfterSeq] returns an iterator
  over substrings of s split after each instance of sep.
- [FieldsSeq] returns an iterator over
  substrings of s split around runs of whitespace characters,
  as defined by unicode.IsSpace.