boolean symbol for or

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

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

JavaScript Symbol type Depending on the specification, the object property key can only be string or symbol type, not number, Boolean, only string and symbol two types.We typically compare attribute string, and now look at the advantages that the

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

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,

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 "= =" Symbol and the Boolean conversion rule in JSWhat is the rules for how = = converts types?Comparison rules for "= =":1. Comparing numbers and strings would always convert the strings to numbers.The number type is compared to the string type,

What is the rules for how = = converts types?Comparison rules for "= =":1. Comparing numbers and strings would always convert the strings to numbers.The number type is compared to the string type, and the string is converted to the number type.

Symbol resolves property name conflicts for objects Remember some of the data types we know. String number Object undefined Null Boolean Now, one more type is symbol. Let A=symbol () Console.log (a)//symbol () Console.log (typeof a)//symbol The code

3.1 symbol table   The main purpose of a symbol table is to associate a key with a value. In this example, you can insert a key-value pair into the symbol table and then find the corresponding value from all the key-value pairs in the symbol table.