Performance

Deno supports user timing Level 3 (see: https://w3c.github.io/user-timing) which is not widely supported yet in other runtimes. These types are here so that these features are still available when using the Deno namespace in conjunction with other type libs, like dom.

interface Performance {

mark(markName: string, options?: PerformanceMarkOptions): PerformanceMark;

measure(measureName: string, options?: PerformanceMeasureOptions): PerformanceMeasure;

}

class Performance extends EventTarget {

constructor();

readonly timeOrigin: number;

clearMarks(markName?: string): void;

clearMeasures(measureName?: string): void;

getEntries(): PerformanceEntryList;

getEntriesByName(name: string, type?: string): PerformanceEntryList;

getEntriesByType(type: string): PerformanceEntryList;

mark(markName: string, options?: PerformanceMarkOptions): PerformanceMark;

measure(measureName: string, options?: PerformanceMeasureOptions): PerformanceMeasure;

measure(

measureName: string,

startMark?: string,

endMark?: string,

): PerformanceMeasure;

now(): number;

toJSON(): any;

}

§Methods

mark(markName: string, options?: PerformanceMarkOptions): PerformanceMark

Stores a timestamp with the associated name (a "mark").

measure(measureName: string, options?: PerformanceMeasureOptions): PerformanceMeasure

Stores the DOMHighResTimeStamp duration between two marks along with the associated name (a "measure").

§Extends

EventTarget

§Constructors

new Performance()

§Properties

timeOrigin: number

Returns a timestamp representing the start of the performance measurement.

§Methods

clearMarks(markName?: string): void

Removes the stored timestamp with the associated name.

clearMeasures(measureName?: string): void

Removes stored timestamp with the associated name.

getEntries(): PerformanceEntryList

getEntriesByName(name: string, type?: string): PerformanceEntryList

getEntriesByType(type: string): PerformanceEntryList

mark(markName: string, options?: PerformanceMarkOptions): PerformanceMark

Stores a timestamp with the associated name (a "mark").

measure(measureName: string, options?: PerformanceMeasureOptions): PerformanceMeasure

Stores the DOMHighResTimeStamp duration between two marks along with the associated name (a "measure").

measure(measureName: string, startMark?: string, endMark?: string): PerformanceMeasure

Stores the DOMHighResTimeStamp duration between two marks along with the associated name (a "measure").

now(): number

Returns a current time from Deno's start in milliseconds.

Use the permission flag --allow-hrtime return a precise value.

const t = performance.now();
console.log(`${t} ms since start!`);

toJSON(): any

Returns a JSON representation of the performance object.