Lookup map in JavaScript

Hey guys! Do you know if statement? Of course yes! But do you know lookup map? It's an elegant way to solve a multiple conditions.

Instead of using if..else, switch, we can define in advance a lookup table of values based on certain key.

Let's look at an example:

	let lang
	let languageFn = code => {
	return{
	"cz":"Czech",
	"us":"English",
	"ja":"Japanese",
	"ru":"Russian",
	"default":"English"
	}[code]
	}
	lang = languageFn( 'ja' ) || languageFn( 'default' )
	console.log( lang )
	//--------------------
	let languageMap = new Map([
	["cz","Czech"],
	["us","English"],
	["ja","Japanese"],
	["ru","Russian"],
	["default","English"]
	])
	lang = languageMap.get("cz") || languageMap.get("default")
	console.log( lang )
	//--------------------
	let languageObj = {
	"cz":"Czech",
	"us":"English",
	"ja":"Japanese",
	"ru":"Russian",
	"default":"English"
	}
	lang = languageObj.abc || languageObj.default
	console.log( lang )

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