It’s a pattern match, “destructuring” something of type &T. That is, in let &x = &1i; x has type int, and value 1. So it’s actually the opposite to ref (which does what @KerrekSB is saying, ref x captures by reference rather than by value). One can regard it as similar to match returns_an_option() { … Read more
A map entry cannot be addressed (as its address might change during map growth/shrink), so you cannot call pointer receiver methods on them. Detail here: https://groups.google.com/forum/?fromgroups=#!topic/golang-nuts/4_pabWnsMp0
There is a major difference between slices and maps: Slices are backed by a backing array and maps are not. If a map grows or shrinks a potential pointer to a map element may become a dangling pointer pointing into nowhere (uninitialised memory). The problem here is not “confusion of the user” but that it … Read more
Pointers are values just like let’s say int numbers. The difference is the interpretation of that value: pointers are interpreted as memory addresses, and ints are interpreted as integer numbers. When you want to change the value of a variable of type int, you pass a pointer to that int which is of type *int, … Read more
There is no such thing as a “pointer to an interface” (technically, you can use one, but generally you don’t need it). As seen in “what is the meaning of interface{} in golang?“, interface is a container with two words of data: one word is used to point to a method table for the value’s … Read more
The error cannot use type []byte as type *[]byte in argument to sliceArr() comes from a typo which you haven’t posted (you tried to pass a slice and not a pointer to a slice to sliceArr()). As to the other error (cannot slice type *[]byte), you just need to use parenthesis to group the pointer … Read more
Rust usually focuses on object value (i.e. the interesting part of the contents) rather than object identity (memory addresses). The implementation of Display for &T where T implements Display defers directly to the contents. Expanding that macro manually for the String implementation of Display: impl<‘a> Display for &’a String { fn fmt(&self, f: &mut Formatter) … Read more
From http://golang.org/ref/spec#Exported_identifiers: An identifier may be exported to permit access to it from another package. An identifier is exported if both: the first character of the identifier’s name is a Unicode upper case letter (Unicode class “Lu”); and the identifier is declared in the package block or it is a field name or method name. … Read more