escargot/docs/Spec.md

Specification

Escargot is lightweight JavaScript engine used in Pando. Escargot implements full of ECMAScript 5.1 specification and part of ECMAScript 6.0 specification.

ES5

ES5 specification is fully supported with Escargot.

ES6

supported

Object type	Implemented Feature	Property Type	Note
TypedArray Objects	TypedArray ()	constructor	Currently it works expectedly only with arraylength less than 210000000
	TypedArray (length)	constructor
	TypedArray (buffer [, byteOffset [, length]])	constructor
	TypedArray.prototype.indexOf (searchElement [, fromIndex])	method
	TypedArray.prototype.lastIndexOf (searchElement [, fromIndex])	method
	TypedArray.prototype.set (array [, offset])	method
	TypedArray.prototype.set (typedArray [, offset])	method
	TypedArray.prototype.subarray ([begin [, end]])	method
	TypedArray.BYTES_PER_ELEMENT	data property
	TypedArray.prototype.BYTES_PER_ELEMENT	data property
	TypedArray.prototype.constructor	data property
	TypedArray.prototype.copyWithin (target, start [, end])	method
	TypedArray.prototype.every (callbackfn [, thisArg])	method
	getter of TypedArray.prototype.byteLength	accessor property
	getter of TypedArray.prototype.byteOffset	accessor property
	getter of TypedArray.prototype.length	accessor property
	getter of TypedArray.prototype.buffer	accessor property
ArrayBuffer Objects	ArrayBuffer (length)	constructor
	ArrayBuffer.isView (arg)	function
	getter of ArrayBuffer.prototype.byteLength	accessor property
	ArrayBuffer.prototype.constructor	data property
	ArrayBuffer.prototype.slice (start, end)	method
DataView Objects	DataView (buffer [, byteOffset [, byteLength]])	constructor
	getter of DataView.prototype.buffer	accessor property
	getter of DataView.prototype.byteLength	accessor property
	getter of DataView.prototype.byteOffset	accessor property
	DataView.prototype.constructor	data property
	DataView.prototype.[get | set][Float32 | Float64 | Int8 | Int16 | Int32 | Uint8 | Uint16 | Uint32] (byteOffset [, littleEndian))	method
Promise Objects	Promise (executor)	constructor
	Promise.all (iterable)	function
	Promise.race (iterable)	function
	Promise.reject (r)	function
	Promise.resolve (x)	function
	Promise.prototype.catch (onRejected)	method
	Promise.prototype.then (onFulfilled, onRejected)	method

Etc.

Even though the features below are not included in ES5 or ES6 specification, Escargot supports them for your usability.

Legacy features

Implemented Feature	Note
Object.prototype.__proto__
Object.prototype.__defineGetter__ (prop, func)
Object.prototype.__defineSetter__ (prop, func)
Object.prototype.__lookupGetter__ (prop)
Object.prototype.__lookupSetter__ (prop)
escape (str)
unescape (str)

Escargot-specific features

Implemented Feature	Function	Note
print (arg)	prints arg on stdout	standalone binary only
load (fileName)	opens a file named fileName and executes the contents as source code	standalone binary only
read (fileName)	opens a file named fileName and returns the contents as string	standalone binary only
run (fileName)	opens a file named fileName, executes the contents as source code, and returns the time spent to execute the code	standalone binary only
gc()	invokes garbage collector