Data typeBefore introducing symbol, let's briefly describe the JavaScript data type:JavaScript has 6 data types, namely:
string literal type
Number numeric type
Object type
Boolean Boolean value type
Null empty value
C ++ Operator Overloading and Operator Overloading
The operation objects of pre-defined operators in C ++ can only be basic data types. However, similar operations are also required for many user-defined types (such as classes. In this case, you
Operator overloading
The so-called overloading, is to re-give new meaning. A function overload is a function that assigns a new meaning to an existing function, enabling it to implement new functionality, so that a function name can be used to
SymbolOverview as symbol instance of property name: Eliminates the traversal of the Magic string property name Symbol.for (), Symbol.keyfor () instance: the Symbol value built into the module's Singleton mode
Overview
ES5 object property names are
ES5 object property names are strings, which can easily cause property names to conflict. For example, if you use an object provided by another person but want to add a new method to the object (mixin mode), the name of the new method may conflict
In Javascript ES6, the use of the data type Symbol is described in detail.
Introduction
Symbol is a special and unchangeable data type. It can be used as an identifier of an object property to indicate unique values. The Symbol object is an implicit
! The operator performs a logical "Non" Operation on the expression.! = The operator compares the values of two expressions to see if they are equal.! = The operator compares the values of two expressions to see if they are not equal or the data
An operator is a particular symbol or expression used to examine, modify, or merge variables. For example, with the sum operator + you can sum two digits (such as let i = 1 + 2); a slightly more complex example has logic and operator && (e.g. if
What is Symbol?
Symbols is not an icon, nor does it mean that you can use a small picture in your code:
Nor does it refer to the grammar of other things. So, what exactly is Symbol to?Seven types of data
When JavaScript was normalized in 1997,
An expression
C + + provides a rich operator and defines what these operators mean when the operands are of a built-in type. In addition, C + + supports operator overloading, allowing programmers to customize the meaning of the operator when used
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