Learning Swift from scratch (day 20)--passing references to parameters in a function

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Passing references to parameters

A class is a reference type, and other data types such as Integer, float, Boolean, character, string, tuple, collection, enumeration, and struct are all value types.

Sometimes it is possible to pass a value type argument as a reference, which is also achievable, Swift provided by inout keyword can be implemented. Look at one of the following examples:

Func increment (inoutvalue:double, amount:double = 1.0) {Value + = amount} var value:double = 10.0 Increment (&valu e) Print (value) increment (&value,amount:100.0) print (value)

code is the calling function & Value & value address "is a way of passing references, which when defining a function , the parameters are identified with the inout is corresponding to each other.

Code Increment (&value,amount:100.0) also called functions Increment , the amount of growth is 100.0 .

The above code output results are as follows:

11.0

111.0

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Learning Swift from scratch (day 20)--passing references to parameters in a function