类型力
Javascript的另一个偏颇类型检查解决方案 .
例外消息可能会在补丁版本之间发生改变,因为补丁经常会改变一些出乎意料的行为,自然会导致不同的错误消息.
实例
var typeforce = require('typeforce')
// supported primitives 'Array', 'Boolean', 'Buffer', 'Number', 'Object', 'String'
typeforce('Array', [])
typeforce('Number', [])
// TypeError: Expected Number, got Array
// array types
typeforce(['Object'], [{}])
typeforce(typeforce.arrayOf('Object'), [{}, {}, {}])
// enforces object properties
typeforce(
{
foo: 'Number',
},
{
foo: 'bar',
}
)
// TypeError: Expected property "foo" of type Number, got String "bar"
// maybe types
typeforce('?Number', 2)
typeforce('?Number', null)
typeforce(typeforce.maybe(typeforce.Number), 2)
typeforce(typeforce.maybe(typeforce.Number), null)
// sum types
typeforce(typeforce.anyOf('String', 'Number'), 2)
typeforce(typeforce.allOf({ x: typeforce.Number }, { y: typeforce.Number }), {
x: 1,
y: 2,
})
// value types
typeforce(typeforce.value(3.14), 3.14)
// custom types
function LongString(value, strict) {
if (!typeforce.String(value)) return false
if (value.length !== 32) return false
return true
}
typeforce(LongString, '00000000000000000000000000000000')
// => OK!
typeforce(LongString, 'not long enough')
// TypeError: Expected LongString, got String 'not long enough'
赞成提示 :
// use precompiled primitives for high performance
typeforce(typeforce.Array, array)
// or just precompile a template
var type = {
foo: 'Number',
bar: '?String',
}
var fastType = typeforce.compile(type)
// fastType => typeforce.object({
// foo: typeforce.Number,
// bar: typeforce.maybe(typeforce.String)
// })
// use strictness for recursive types to enforce whitelisting properties
typeforce(
{
x: 'Number',
},
{ x: 1 },
true
)
// OK!
typeforce(
{
x: 'Number',
},
{ x: 1, y: 2 },
true
)
// TypeError: Unexpected property 'y' of type Number
赞成提示( 扩展类型 ) :
typeforce(typeforce.tuple('String', 'Number'), ['foo', 1])
// OK!
typeforce(typeforce.tuple('Number', 'Number'), ['not a number', 1])
// TypeError: Expected property "0" of type Number, got String 'not a number'
typeforce(typeforce.map('Number'), {
anyKeyIsOK: 1,
})
// OK!
typeforce(typeforce.map('Number', typeforce.HexN(8)), {
deadbeef: 1,
ffff0000: 2,
})
// OK!
function Foo() {
this.x = 2
}
typeforce(typeforce.quacksLike('Foo'), new Foo())
// OK!
// Note, any Foo will do
typeforce(typeforce.quacksLike('Foo'), new (function Foo() {})())
// OK!
赞成提示( 无抛出)
var typeforce = require('typeforce/nothrow')
var value = 'foobar'
if (typeforce(typeforce.Number, value)) {
// didn't throw!
console.log(`${value} is a number`) // never happens
} else {
console.log(`Oops, ${typeforce.error.message}`)
// prints 'Oops, Expected Number, got String foobar'
}
赞成提示( 同步)
var typeforce = require('typeforce/async')
typeforce(typeforce.Number, value, function (err) {
if (err) return console.log(`Oops, ${typeforce.error.message}`)
console.log(`${value} is a number`) // never happens
})
警告:对使用 quacksLike 类型,因为它依赖于 Foo.name 属性.
如果该财产被转接者所操纵,例如: uglifyjs你会有一个糟糕的时间.