pointers - Why i cant apply address operator (&) to functions return values directly -


this question has answer here:

i don't why following code snippet isn't compiling. compiler states:

cannot take address of getastring()

code:

func getastringpointer() *string {     return &getastring() }  func getastring() string {     return "" }

but, storing results of function in auxliary variable , return address of variable compiler behaves ok.

func getastringpointer() *string {     var astring = getastring()     return &astring }  func getastring() string {     return "" }

you can't apply & value (unless it's composite literal). spec:

for operand x of type t, address operation &x generates pointer of type *t x. operand must addressable, is, either variable, pointer indirection, or slice indexing operation; or field selector of addressable struct operand; or array indexing operation of addressable array. exception addressability requirement, x may (possibly parenthesized) composite literal. if evaluation of x cause run-time panic, evaluation of &x too.


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