Constants are values that are known at compile time and cannot be modified. They are declared using the :: operator.
Constants can be declared at package scope or inside procedures. They are commonly used for values that never change, such as mathematical values and configuration data.
Numeric constants are untyped until the compiler needs a concrete type. This allows constant expressions to be evaluated with arbitrary precision before being converted to the required type.
$ odin run constants.odin -file constant 6e+11 600000000000 600000000000.0
package main import "core:fmt" // Package-level constants. message :: "constant" n :: 500000000 main :: proc() { // Constants behave like any other value. fmt.println(message) // Constant expressions are evaluated at compile time. d :: 3e20 / n fmt.println(d) // Convert an untyped numeric constant to i64. fmt.println(i64(d)) // The same constant can be converted to a different type. fmt.println(f64(d)) }