return at === -1 ? [str] : [str.substring(0, at)].concat(splitN(str.substring(at + delimiter.length), delimiter, limit - 1));
}
+// A clock that never goes backwards; monotonic.
+function Clock() {
+ var previousNow = Date.now();
+ return {
+ now: function (): number {
+ const now = Date.now();
+ if (now > previousNow) {
+ previousNow = now;
+ return now;
+ }
+ return ++previousNow;
+ },
+ };
+}
+const clock = Clock();
+
const Model = {
addTask: function (timestamp: string, description: string): Element {
const task = document.createElement("div");
const UI = {
addTask: function (description: string): Element {
- const now = Date.now();
+ const now = clock.now();
undoLog.push(`State ${now} deleted`);
return <Element>log.recordAndApply(`${now} Create ${description}`);
},
edit: function (createTimestamp: string, newDescription: string, oldDescription: string) {
undoLog.push(`Edit ${createTimestamp} ${oldDescription}`);
- return log.recordAndApply(`${Date.now()} Edit ${createTimestamp} ${newDescription}`);
+ return log.recordAndApply(`${clock.now()} Edit ${createTimestamp} ${newDescription}`);
},
setPriority: function (createTimestamp: string, newPriority: number, oldPriority: number) {
undoLog.push(`Priority ${createTimestamp} ${oldPriority}`);
- return log.recordAndApply(`${Date.now()} Priority ${createTimestamp} ${newPriority}`);
+ return log.recordAndApply(`${clock.now()} Priority ${createTimestamp} ${newPriority}`);
},
setState: function (createTimestamp: string, newState: string, oldState: string) {
undoLog.push(`State ${createTimestamp} ${oldState}`);
- return log.recordAndApply(`${Date.now()} State ${createTimestamp} ${newState}`);
+ return log.recordAndApply(`${clock.now()} State ${createTimestamp} ${newState}`);
},
undo: function () {
if (undoLog.length > 0) {
- return log.recordAndApply(`${Date.now()} ${undoLog.pop()}`);
+ return log.recordAndApply(`${clock.now()} ${undoLog.pop()}`);
}
},
};
// Change task's priority to be between other tasks a and b.
setPriority: function (task: Element, a: Element | null, b: Element | null) {
const aPriority = a === null ? 0 : Model.getPriority(a);
- const bPriority = b === null ? Date.now() : Model.getPriority(b);
+ const bPriority = b === null ? clock.now() : Model.getPriority(b);
console.assert(aPriority < bPriority, aPriority, "<", bPriority);
const span = bPriority - aPriority;
const newPriority = aPriority + 0.1 * span + 0.8 * span * Math.random();