In Go, a pointer is a variable that holds the memory address of another variable, while a value is the actual data stored at a particular memory location.
Pointers and values differ in terms of how they can be used and manipulated in the code. Here are some notable differences:
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Assignment: A value can be directly assigned to a variable, while a pointer needs to be assigned the memory address of a variable.
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Dereferencing: When a pointer variable is used in an expression, it needs to be dereferenced using the * operator to access the value it points to. A value, on the other hand, can be directly accessed without any additional operators.
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Passing as arguments: A value is passed by value, which means that a copy of the data is passed to the function. A pointer, however, is passed by reference, which means that the memory address of the data is passed to the function. This allows the function to modify the original data.
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Nullability: A pointer can have a null value (nil) which indicates that it does not point to any valid memory location. A value cannot have a null value.
Overall, pointers and values serve different purposes in Go, and their usage depends on the specific requirements of the program.