1const x = 1234;
 2
 3fn foo() void {
 4    // It works at file scope as well as inside functions.
 5    const y = 5678;
 6
 7    // Once assigned, an identifier cannot be changed.
 8    y += 1;
 9}
10
11pub fn main() void {
12    foo();
13}
14
15// exe=build_fail