@aboutweb/proxyscope 中文文档教程
ProxyScope
Bootstrap 将对象与 ES 代理相结合,并在其他代理工厂上重用它们。 这也将反映对原始对象所做的更改。 在使用不可变对象或混合对象时,代理也很有用。
Install
npm i @aboutweb/proxyscope
ProxyFactory(`…(traps || factory))
traps
为新代理
factory
合并的陷阱链 先前创建的工厂
返回具有 traps
属性的 factory
函数
factory(Object target | Array<Object target>
, ...traps
)
target
用作查找堆栈的对象或对象数组
traps
在创建新代理时组合
Example
import { default as proxyFactory } from "@aboutweb/proxyscope";
import otherFactory from "./otherfactory.js";
const traps = {
has(target, property, receiver) {
return this.findHost(property);
},
/*helper method*/
findHost(property, root) {
let host = this.stack.find(function(level) {
return property in level;
});
if(host) {
return host;
}
if(root === true) {
return this.stack[0];
}
}
}
const factory = proxyFactory(traps, otherfactory);
export {
factory as default,
traps
}
ProxyScope.read
使用 target.stack
查找特性。
Example
import { read as proxyRead } from "@aboutweb/proxyscope";
let defaultConfig = {
fu : "bar"
}
function someFn(config) {
let proxy = proxyRead(config, defaultConfig);
expect(proxy.fu).to.equal("bar");
expect(proxy.bar).to.equal("baz");
}
someFn({
bar : "baz"
});
ProxyScope.write
与 proxyRead 相同,但如果它们在级别链中的某处定义,也会转发写入。
Example
const l1 = {
some : "value"
}
const l2 = {
fu : "bar"
}
let proxy = proxyWrite(l1, l2);
proxy.fu = "hallo";
expect(l2.fu).to.equal("hallo");
ProxyScope.readDeep
甚至读取嵌套对象,通过为每个具有多个可能的 getter 的属性返回一个新代理来扩展代理读取
明智地使用,因为这将为每个具有多个可能值的属性查找创建一个代理。 因此,建议尽可能缓存查找。
Example
import { readDeep as proxyReadDeep } from "@aboutweb/proxyscope";
const l1 = {
nested : {
some : "value",
}
}
const l2 = {
nested : {
fu : "bar"
}
}
const l3 = {
other : true
}
let proxy = proxyReadDeep(l1, l2, l3);
//before caching or update cache afterwords
l3.nested = {
deep : true
}
//cache the returned proxy
let nested = proxy.nested;
expect(nested.some).to.equal("value");
expect(nested.fu).to.equal("bar");
expect(nested.deep).to.equal(true);
ProxyScope.writeDeep
与 proxyReadDeep 相同,但也会写入嵌套对象
Example
import { writeDeep as proxyWriteDeep } from "@aboutweb/proxyscope";
const l1 = {
nested : {
some : "value",
}
}
const l2 = {
nested : {
fu : "bar"
}
}
let proxy = proxyReadDeep(l1, l2);
//also use cache where possible
let nested = proxy.nested;
nested.some = "other";
nested.fu = "baz";
expect(l1.nested.some).to.equal("other");
expect(l2.nested.fu).to.equal("baz");
Licence
ISC
ProxyScope
Bootstrap for combining object be reference with ES proxy, and reusing them on other proxy-factories. Which will also reflect changes made to the original objects. Proxies can also be useful when using immutables or mixins.
Caution this method uses Proxies and therefor will only work in modern enviroments. Please view CanIUse for more information.
Install
npm i @aboutweb/proxyscope
Caution this method uses Proxies and therefor will only work in modern enviroments. Please view CanIUse for more information.
ProxyFactory(`…(traps || factory))
traps
chain of traps merged for the new Proxy
factory
a previous created factory
returns a factory
function with a traps
property
factory(Object target | Array<Object target>
, ...traps
)
target
an object or array of object to use as stack for lookups
traps
to combine while creating a new proxy
Example
import { default as proxyFactory } from "@aboutweb/proxyscope";
import otherFactory from "./otherfactory.js";
const traps = {
has(target, property, receiver) {
return this.findHost(property);
},
/*helper method*/
findHost(property, root) {
let host = this.stack.find(function(level) {
return property in level;
});
if(host) {
return host;
}
if(root === true) {
return this.stack[0];
}
}
}
const factory = proxyFactory(traps, otherfactory);
export {
factory as default,
traps
}
ProxyScope.read
Uses the target.stack
to look up properties.
Example
import { read as proxyRead } from "@aboutweb/proxyscope";
let defaultConfig = {
fu : "bar"
}
function someFn(config) {
let proxy = proxyRead(config, defaultConfig);
expect(proxy.fu).to.equal("bar");
expect(proxy.bar).to.equal("baz");
}
someFn({
bar : "baz"
});
ProxyScope.write
same as proxyRead but will also forward writes if they are defined somewhere in the level chain.
Example
const l1 = {
some : "value"
}
const l2 = {
fu : "bar"
}
let proxy = proxyWrite(l1, l2);
proxy.fu = "hallo";
expect(l2.fu).to.equal("hallo");
ProxyScope.readDeep
read even nested objects, extends proxy-read by returning a new proxy for every property that has multiple possible getters
Use wisely, because this will create a proxy for every property lookup that has more then one possible value. Therefor it is recommended to cache lookups when possible.
Example
import { readDeep as proxyReadDeep } from "@aboutweb/proxyscope";
const l1 = {
nested : {
some : "value",
}
}
const l2 = {
nested : {
fu : "bar"
}
}
const l3 = {
other : true
}
let proxy = proxyReadDeep(l1, l2, l3);
//before caching or update cache afterwords
l3.nested = {
deep : true
}
//cache the returned proxy
let nested = proxy.nested;
expect(nested.some).to.equal("value");
expect(nested.fu).to.equal("bar");
expect(nested.deep).to.equal(true);
ProxyScope.writeDeep
same as proxyReadDeep, but will also write to nested objects
Example
import { writeDeep as proxyWriteDeep } from "@aboutweb/proxyscope";
const l1 = {
nested : {
some : "value",
}
}
const l2 = {
nested : {
fu : "bar"
}
}
let proxy = proxyReadDeep(l1, l2);
//also use cache where possible
let nested = proxy.nested;
nested.some = "other";
nested.fu = "baz";
expect(l1.nested.some).to.equal("other");
expect(l2.nested.fu).to.equal("baz");
Licence
ISC