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factory functions vs decorator

const comicBookCharacter = ( first, last ) => {
const firstName = first
const lastName = last
return {
realName: `${firstName} ${lastName}`
}
}
const superPower = ( ref ) => {
let powers = []
return {
addPower: ( p ) => {
powers.push( p )
return ref
},
powers
}
}
const utilityBelt = ( ref ) => {
let utilities = []

return {
addToBelt: ( p ) => {
utilities.push( p )
return ref
},
utilities
}
}
const decorate = ( obj, factoryArray ) => {
const instances = factoryArray.map( f => f( obj ) )
return Object.assign( obj, …instances )
}
let batman = comicBookCharacter( ‘Bruce’, ‘Wayne’ )console.log( batman.realName )decorate( batman, [ superPower, utilityBelt ] )batman
.addPower( ‘money’ )
.addToBelt( ‘something’ )
.addPower( ‘strength’)
.addToBelt( ‘batarang’ )
console.log( batman.powers, batman.utilities )

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