Go Learning Notes: Constants

This is a creation in Article, where the information may have evolved or changed.

Go supports defining character constants, string constants, Boolean constants, and numeric constants.

Use const keywords to define constants.

package mainimport  "FMT" import  "math"   "Const"   keyword to define constants const s string =  "Constant" func main ()  {     fmt. Println (s)     //  "const" keywords can appear where any "var" keyword appears     //  The difference is that constants must have initial values     const n = 500000000    //  Constant expressions can perform mathematical calculations of arbitrary precision     const d = 3e20 / n     Fmt. Println (d)     //  numeric constants do not have a specific type unless you specify a type     //  such as explicit type conversion      fmt. PRINTLN (Int64 (d))     //  numeric constants can get types in the logical context of a program     //  such as variable assignment or function invocation.     //  For example, for the sin function in the math package, it requires a variable     fmt of type float64. Println (Math. Sin (n))} 

The output result is

constant6e+11600000000000-0.2847040732381611