go / beginner
Snippet
Methods with Pointer Receivers
Methods can be defined with value receivers `(*Counter)` or pointer receivers. Pointer receivers modify the original struct, while value receivers work on a copy. For mutable operations, always use pointer receivers.
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package mainimport "fmt"type Counter struct {value int}func (c *Counter) Increment() {c.value++}func (c Counter) Value() int {return c.value}func (c *Counter) Add(n int) {c.value += n}func main() {c := Counter{value: 10}c.Increment()c.Add(5)fmt.Printf("Counter: %d\n", c.Value())}
Breakdown
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func (c *Counter) Increment()
Pointer receiver allows mutation of c.value
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func (c Counter) Value() int
Value receiver, safe for read-only operations
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c.Increment()
Go automatically takes address of c when calling pointer method
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c.Add(5)
Modifies the original struct via pointer receiver