arrow.md

let f = (a, [b]) => ({a, b})

f(1, [true]) //:: {a: number, b: bool}

function wrap() {
  return () => (this //:: {a: number}
               )
}
wrap.call({a: 10}).call({b: true}) //:: {a: number}

function Obj() {
  this.x = true
}
Obj.prototype.map = function() {
  return [1, 2, 3].map(e => this.x)
}

;(new Obj).map() //: [bool]

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f	__DIR__/arrow.js	/f/;"	f	lineno:1	type:f.!ret function(number, Array[bool])
a	__DIR__/arrow.js	/a/;"	v	lineno:1	namespace:f	type:number
b	__DIR__/arrow.js	/b/;"	v	lineno:1	namespace:f	type:boolean
wrap	__DIR__/arrow.js	/wrap/;"	f	lineno:5	type:wrap.!ret.!ret function() function()
Obj	__DIR__/arrow.js	/Obj/;"	f	lineno:11	type:void function()
map	__DIR__/arrow.js	/map/;"	f	lineno:14	namespace:Obj.prototype	type:[!this.x] function()