c3-util

这是c3一些class的公共类

Optinal类

Optional用于包装对象是否为空,当某个方法会具体对象也有可能返回空时，通过Optial封装可以提醒调用者这个方法有可能返回空要对空进行处理

• import 方法

import { Optional } from 'c3-util'

• 创建 Optional objects

const nullableString: string | null = /* some nullable value */;

// all the following variables will be parameterized as Optional<string>.
const optional = Optional.ofNullable(nullableString);
const optionalPresent1 = Optional.ofNullable("foo");
const optionalPresent2 = Optional.ofNonNull("foo"); // accepts non-null value (or else throws TypeError)
const optionalEmpty1: Optional<string> = Optional.empty(); // type hinting required
const optionalEmpty2 = Optional.empty<string>(); // or parameterize explicitly

• Optional的方法

const optional: Optional<string> = Optional.ofNullable( /* some optional value: null | string */ );

// force to retrieve the payload. (or else throws TypeError.)
// this method is not used match.
optional.get();

// represent whether this is present or not.
optional.isPresent();

// represent whether this is empty or not. (negation of `isPresent` property)
optional.isEmpty();

// if a payload is present, execute the given `consumer`.
optional.ifPresent(value => console.log(value));

// if a payload is present, execute the first argument (`consumer`),
// otherwise execute the second argument (emptyAction).
optional.ifPresentOrElse(value => console.log(value), () => console.log("empty"));

// filter a payload with additional predicate.
optional.filter(value => value.length > 0);

// map a payload with the given mapper.
optional.map(value => value.length);

// map a payload with the given mapper which returns value wrapped with Optional type.
const powerIfPositive: (x: Number) => Optional<Number>
    = x => (x > 0) ? Optional.ofNonNull(x * x) : Optional.empty();
const numberOptional: Optional<null | number> = Optional.ofNullable(/* some optional value: null | number */)
numberOptional.flatMap(value => powerIfPositive(value as number));

// if this is present, return this, otherwise return the given another optional.
const another: Optional<string> = Optional.ofNullable(/* ... */);
optional.or(another);

// if this is present retrieve the payload,
// otherwise return the given value.
optional.orElse("bar");

// if a payload is present, retrieve the payload, 
// otherwise return a value supplied by the given function.
optional.orElseGet(() => "bar");

// if a payload is present, retrieve the payload,
// otherwise throw an exception supplied by the given function.
optional.orElseThrow(() => new Error());

// if a payload is present, retrieve the payload,
// otherwise return null.
optional.orNull();

// if a payload is present, retrieve the payload,
// otherwise return undefined.
optional.orUndefined();

// return an appropriate result by emulating pattern matching with the given cases.
optional.matches({
    present: value => value.length,
    empty: () => 0, 
})

// convert this to an Option value.
optional.toOption();

Crypt类

Crypt是用于加密算法类,支持md5，还有一些加密算法还没弄清楚，不知道是否支持des

• import 方法

import { Crypt } from 'c3-util'

• 方法

const mdrStr=Cypt.hex_md5('112345')