JavaScript/Reserved words
In JavaScript, some tokens (words) have a special semantic (meaning). Therefore they cannot be used as names of variables, functions, classes, etc [1] [2]. Some of them are generally reserved words; others are reserved only in a special context; others are reserved for possible future usage without having a special functionality nowadays; others have been defined in outdated ECMAScript versions of the years 1997 - 99.
The list of such special words as of 2022 follows. For some of the words, we offer further information.
- abstract
- await
- boolean
- break
- byte
- case
- catch
- char
- class
- const
- continue
- debugger
- default
- delete
- do
- double
- else
- enum
- export
- extends
- false
- final
- finally
- float
- for
- function
- goto
- if
- implements
- import
- in
- instanceof
- int
- interface
- let
- long
- native
- new
- null
- package
- private
- protected
- public
- return
- short
- static
- super
- switch
- synchronized
- this
- throw
- throws
- transient
- true
- try
- typeof
- var
- void
- volatile
- while
- with
- yield
Furthermore, there are predefined methods like forEach(), predefined modules like Math, or predefined objects like BigInt whose names should be avoided also.