在Go中将varName设为int64？

Question

How do I write the equivalent of Dim varName as int64 = value in Go?

Whenever I find myself needing to declare a variable in Go I google a lot until I find the correct syntax.

Answer 1

Using a variable declaration (can be used inside functions and at the top level to create global variables):

var i int64 = value

If value is a typed int64 value, you may omit the type which will be inferred:

var i2 = value // type is inferred

Short variable declaration (may only appear inside function bodies):

i3 := value // type is inferred

Notes:

Both with the variable declaration (without type) and with short variable declaration care must be taken if you use a value with different type - or an untyped constant. In these cases explicit type conversion may be required in order for the new variable to get the proper int64 type!

var i4 = 4        // Wrong! i4 will be of type int
var i5 = int64(4) // Good! i5 will be of type int64
var i6 int64 = 4  // Also good: explicitly provided type
i7 := 4           // Wrong! i4 will be of type int
i8 := int64(4)    // Good! i5 will be of type int64