Reflect.defineMetadata | /src/injection/reflect.ts | alosaur@v0.35.1

function Reflect.defineMetadata

import { Reflect } from "https://deno.land/x/alosaur@v0.35.1/src/injection/reflect.ts";
const { defineMetadata } = Reflect;

defineMetadata(

metadataKey: any,

metadataValue: any,

target: any,

): void

Define a unique metadata entry on the target.

defineMetadata(

metadataKey: any,

metadataValue: any,

target: any,

propertyKey: string | symbol,

): void

Define a unique metadata entry on the target.

Examples

class Example { }

// constructor Reflect.defineMetadata("custom:annotation", options, Example);

// decorator factory as metadata-producing annotation.
function MyAnnotation(options): ClassDecorator {
    return target => Reflect.defineMetadata("custom:annotation", options, target);
}

Parameters

metadataKey: any

A key used to store and retrieve metadata.

metadataValue: any

A value that contains attached metadata.

target: any

The target object on which to define metadata.

Returns

void

Define a unique metadata entry on the target.

Examples

class Example { // property declarations are not part of ES6, though they are valid in TypeScript: // static staticProperty; // property;

static staticMethod(p) { } method(p) { } }

// property (on constructor)
Reflect.defineMetadata("custom:annotation", Number, Example, "staticProperty");

// property (on prototype)
Reflect.defineMetadata("custom:annotation", Number, Example.prototype, "property");

// method (on constructor)
Reflect.defineMetadata("custom:annotation", Number, Example, "staticMethod");

// method (on prototype)
Reflect.defineMetadata("custom:annotation", Number, Example.prototype, "method");

// decorator factory as metadata-producing annotation.
function MyAnnotation(options): PropertyDecorator {
    return (target, key) => Reflect.defineMetadata("custom:annotation", options, target, key);
}

Parameters

metadataKey: any

A key used to store and retrieve metadata.

metadataValue: any

A value that contains attached metadata.

target: any

The target object on which to define metadata.

propertyKey: string | symbol

The property key for the target.

Returns

void