Implicit default value of VS parameter

Question

There are at least two methods in Scala to pass a default value to a method

1) default parameter value

scala> def f(i: Int = 0) = i
f: (i: Int)Int

scala> f()
res0: Int = 0

scala> f(1)
res1: Int = 1

2) implicit parameter

scala> def g(implicit i: Int) = i
g: (implicit i: Int)Int

scala> implicit val default = 0
default: Int = 0

scala> g(1)
res5: Int = 1

scala> g
res7: Int = 0

In which case do you choose one or the other? With the power of implicit defaults, are they useful?

Answer 1

You must be sure to select the default setting.

• You should never create or use implicit parameters of generic types, such as Intor String. See Quote below.
• The default value is the simplest solution. In terms of the complexity of language features.
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listen("localhost")   //will use 41000

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