Native object, built-in object, Host object, host environment

Ecma262:

Host environment:

Host environment:ProgramFor example, C #'s CLR is executed a lot.Programming LanguageEnvironment, for example, running browsers, operating systems, and other operating environments of the script language, for example, a ghost is often seen in Chinese Ghost movies, the host environment is known as the host environment, and the host environment is the same as the host environment. There are many different types of browsers with different standards, so that we can writeCodeWe should try our best to be compatible with various situations and make painstaking efforts. After the death, we may not have a good end, BS.

4.3.6 native object

Object in an ecmascript implementation whose semantics are fully defined by this specification rather than by the host environment.

Note

Standard native objects are defined in this specification. Some native objects are built-in; others may be constructed during the course of execution of an ecmascript program.

Local object:

Local objects referEcmascript implementationAny object provided and independent from the host environment.

Note:

This specification defines standard local objects. Some local objects are built in; others may be created during ecmascript Program Execution

Ex:

Object, function, array, String, Boolean, number,

Date, Regexp, error, evalerror, rangeerror,

Referenceerror, syntaxerror, typeerror, urierror ........

 

4.3.7 built-in object

Object supplied by an ecmascript implementation, independent of the host environment, that is present at the start of the execution of an ecmascript program.

Note

Standard built-in objects are defined in this specification, and an ecmascript implementation may specify and define others. every built-in object is a native object. a built-in constructor is a built-in object that is also a constructor.

Built-in object:

Built-in objects are objects provided by ecmascript and independent from the host environment.

Note:

This specification defines standard built-in objects. An ecmascript implementation may also specify and define other built-in objects. All built-in objects are local objects.

Built-in objects do not need to be instantiated, or they can be directly used without new. Ecmascript defines two built-in objects:

Global and math (they are also local objects. According to the definition, each built-in object is a local object ).

[For details about global object, seeECMA-262.15.1 the Global Object]

4.3.8 Host Object

Object supplied by the host environment to complete the execution environment of ecmascript.

Note

Any object that is not native is a host object.

A host object is an object provided by ecmascript to make the execution environment of ecmascript complete.

All non-local objects are host objects. Dom, BOM, custom object