Golang Index

Interfaces

Interfaces in Go (and most languages that offer interfaces) are:

• A set of method signatures

package main

type Runner interface {
	SetStatement(stmt string)
	Run() error
}

Types implement an interface by implicitly implementing it’s methods. No need to declare that your Type implements an interface. The type implements an interface if it simply implements it’s methods.

Pointers and functions implement interfaces as they are Types themselves.

package main

type Runner interface {
	SetStatement(stmt string)
	Run() error
}

type CassandraRunner struct {
	Config string
}

func (cr *CassandraRunner) SetStatement(stmt string) {
    // do something
}

func (cr *CassandraRunner) Run() {
    // do something
}

Example Code

• Go Playground
• Source: interfaces.go

Resources

• Effective Go: Interfaces
• Go by Example: Interfaces
• Best Practices / Patterns
  • Accept Interfaces and return concrete types