Pointers

Intermediate · Types & Methods

A pointer holds the memory address of a value. &x takes an address; *p dereferences. Pointers let functions mutate the caller’s data and avoid copying large structs.

• pointers1 — read/write an int through *p
• pointers2 — mutate a struct via *Struct
• pointers3 — value copy vs pointer: only a pointer reaches the caller

Resources

• A Tour of Go: Pointers
• Go by Example: Pointers
• Effective Go: Pointers vs. Values

Exercises

pointers1 test

A pointer holds the address of a value. &x takes the address; *p reads or

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Dereference with * to write through the pointer:

*p = *p * 2

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pointers2 test

Passing a *struct lets a function mutate the caller’s struct. Go

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Go auto-dereferences a struct pointer for field access:

a.Balance += amount

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pointers3 test

A value parameter receives a COPY, so changes don’t reach the caller.

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Increment the field through the pointer receiver:

c.N++

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