Why Can't I Get the Address of a String Literal in Go?

Addressing String Literals in Go

In applications involving frequent passing of references to static strings, memory allocation concerns arise. This article addresses the reason behind the inability to obtain the address of string literals and explores potential solutions.

Why Address Retrieval Fails

Retrieving the address of a string literal is not feasible in Go due to ambiguous semantics. The language distinguishes between taking the address of the constant value itself, which could alter the value and potentially lead to runtime errors, and allocating a new object, copying the constant, and acquiring the address of this new version.

Unlike the literal in the provided test1(), test2() demonstrates a valid approach. By utilizing an existing variable with明確ly defined semantics, Go avoids the ambiguity associated with literals. However, this approach would not apply to constants, further emphasizing the prohibition against literal address retrieval.

Optimal Solution: test2()

The recommended solution is to utilize the test2() approach. Although it may require slightly more verbose code, it aligns with Go's clear and concise rules around address retrieval. By creating a dedicated variable and taking the address of this variable, the need for literal addressing is circumvented.

Exception: Composite Literals

An exception to the general rule exists in the case of composite literals, which enable the creation and addressing of anonymous structures. This exception, outlined in the language specification, allows for code such as:

func f() interface{} {
    return &struct {
        A int
        B int
    }{1, 2} 
}

While this exception provides an alternative means of address retrieval, the clarity and simplicity of the test2() solution remain the preferred approach for most scenarios.

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