The reserved words of JavaScript are: abstract, double, goto, native, static, boolean, enum, implements, package, super, byte, char, class, const, public, etc.
The operating environment of this tutorial: windows7 system, javascript version 1.8.5, Dell G3 computer.
Reserved words of JavaScript
Reserved words are a set of names (or commands) prepared for use within the JavaScript language. These names currently have no specific purpose and are reserved for JavaScript upgrades. Users are advised not to use them. Specific instructions are shown in the table.
abstract | double | goto | native | static |
enum | implements | package | super | |
export | import | private | synchronized | |
extends | int | protected | throws | |
final | interface | public | transient | |
#float | long | short | volatile |
- In non-strict mode, only class, const, enums, export, extends, import, and super are reserved words, and other ECMAScript 3 reserved words can be used freely;
- In strict mode, ECMAScript 5 becomes more cautious and strictly limits the use of implements, interface, let, package, private, protected, public, static, yield, eval (non-reserved words), arguments (non-reserved words) .
- JavaScript predefines many global variables and functions, and users should avoid using them. The specific instructions are as shown in the table.
encodeURL | Infinity | Number | RegExp | ##Array |
isFinite | Object | String | Boolean | |
isNaN | parseFloat | SyntaxError | Date | |
JSON | parseInt | TypeError | decodeURL | |
Math | RangeError | undefined | ##decodeURLComponent | |
NaN | ReferenceError | URLError |
Whether in strict mode or non-strict mode, do not use the reserved words listed above when defining variable names, function names, or attribute names. [Related recommendations:javascript learning tutorial]
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