memory_safe.zig

memory_safe.zig

// Memory-safe and leak-free Zig
// By using no heap allocation
// All data is in the single state var, allocated up-front
// Also thread-safe by being single thread (if concurrency needed, use separate message queue/pipes)

const std = @import("std");

const Employee = struct {
    id: i32,
    name: [10]u8,
    salary: f32,
};
const Employees = enum { e1, e2 }; // need to know max num of employees in advance
const Days = enum { mon, tues, wed };

pub fn main() void {
    const state = struct {
      
      var employees: [2]Employee = undefined; // should init deterministically here
      
      fn getEmployee(e: Employees) *Employee {
          return (&employees[@intFromEnum(e)]);
      }
    };
    state.getEmployee(Employees.e1).id = 1;
    @memcpy(&state.getEmployee(Employees.e1).name, "hans      ");
    
    std.debug.print("id: {s}",.{state.getEmployee(Employees.e1).name});
}