verbose function
Prints some verbose message in output.
Implementation
void verbose(String message) {
final sink = _messagesSink;
final lines = message.split('\n');
for (var i = 0; i < lines.length; i++) {
final line = lines[i];
final prefix = i == 0 ? _kVerbosePrefix : _verboseIndent;
sink.writeln('$prefix$line');
}
}