Numeric Enums with Tables

Here is the constant-table pattern in full. Pick a PascalCase table name, give each member an explicit number, and from then on the code speaks in names:

local UserRole = {
    Admin = 1,
    Editor = 2,
    Viewer = 3,
}

Unlike TypeScript's enum, nothing is auto-numbered. You choose every value. Starting from 1 fits Lua's conventions nicely, but any scheme works (HTTP-style codes like 200 and 404 are fine too).

Members shine in comparisons. A function that receives a role can branch on the named constants instead of bare numbers:

local function checkPermissions(role: number)
    if role == UserRole.Admin then
        print("Full access granted")
    elseif role == UserRole.Editor then
        print("Edit access granted")
    else
        print("View access only")
    end
end

Note the parameter is typed number: the table pattern alone doesn't restrict which numbers are allowed. That guarantee is exactly what literal unions add in the next lesson.