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A variable of an interface type can hold a value of any type that implements the methods that are specified in the interface. You don't need to explicitly "declare" that the type "implements" the interface or anything like that -- the compatibility is purely structural based on the methods. |
A variable of an interface type can hold a value of any type that implements the methods that are specified in the interface. You don't need to explicitly "declare" that the type "implements" the interface or anything like that -- the compatibility is purely structural based on the methods. |
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<lang go>package main |
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import "fmt" |
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type Beast interface { |
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Cry() string |
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} |
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type Pet struct{} |
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type Cat struct { |
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Pet |
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} |
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func (p Pet) Name(b Beast) { |
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fmt.Println(b.Cry()) |
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} |
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func (p Pet) Cry() string { |
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return "Woof" |
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} |
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func (c Cat) Cry() string { |
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return "Meow" |
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} |
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func main() { |
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p := Pet{} |
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c := Cat{} |
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p.Name(p) // prt Woof |
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c.Name(c) // prt Meow |
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}</lang> |
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=={{header|Groovy}}== |
=={{header|Groovy}}== |
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