Avoiding the go language from the design interface{} = Nil Judgment error-prone simple method

This is a created article in which the information may have evolved or changed.

The interface{} of the go language is essentially a structure that contains a type field and a pointer field.

Many beginners compare the interface{} with nil, which has been given the type in some cases, and are surprised to find that they are not equal.

In fact, from the design, we can easily avoid this problem, that is, the use of Go function multiple return value characteristics, after the general return value to add an OK bool type return value, can be.

When used, it is only a matter of determining whether the last return value OK is equal to true, and perfectly avoids the hassle of getting into X's potentially typed information.

Students who have doubts about this can compare the following two scenarios:

It is because any pointer assigned to interface{}, the Type information field of interface{} will be filled, so it is not equal to nil. Let's look at the following example:

The variable t is a null pointer, after assigning to I, I is not equal to nil.

For a clear and readable code, I recommend using the function return value design recommended at the beginning of this article to circumvent the pitfalls described in this article.