Starts the StopWatch.
start should not be called if the StopWatch is already running.
import core.thread : Thread; StopWatch sw; assert(!sw.running); assert(sw.peek() == Duration.zero); sw.start(); assert(sw.running); Thread.sleep(usecs(1)); assert(sw.peek() > Duration.zero);
See Implementation
Starts the StopWatch.
start should not be called if the StopWatch is already running.