Suggestion: Reusable formula in Lua

[名前이름]

Hey everyone,

Hello, I'm new here, so I'm sorry if I wasn't clear or posted this in the wrong area. I just had an idea I thought might be useful or practical for Lua, where you have a variable having a value of a math formula, and within that formula are different variables being used. And then, in the same code, you may encounter a situation where you can reuse the same math formula. Instead of manually creating another variable with the same formula, you can reuse the predefined variable and a function to replace the variables with different ones. It’d make stuff like game scripting, math simulations, or quick prototyping a lot easier, kinda like reusable expressions.

Does something like this already exist or sound possible to implement?

Thanks!

[Андрей Закатов]

I guess I did not really understand you well enough, but what is stopping you from making your function a global, just passing the argument in there.

Or do you want something more like a closure, like this?

function greeter(prefix)

  return function(name)

    return string.format("Hello, %s %s",prefix,name)

  end

end

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[Scott Morgan]

It sounds like you're just talking about functions. Can you give an
example of what you're thinking about?

Scott

[Sewbacca]

Sure, let's say you want to calculate the volume of a cylinder, which is the area of the radius times the circle (I'm just contriving an example to make a point):

local volume = h * math.pi * r^2

If you want to reuse the circle equation just define a function

local function circlearea(r)
    return math.pi * r^2
end

and you can reuse the calculation of the circle for the volume like this:

local volume = h * circlearea(r)

[名前이름]

What if it's a long formula, custom formula specifically that you didn't even know you would need it again only until now

[Martin Eden]

On 2025-10-24 06:10, 名前이름 wrote:
> What if it's a long formula, custom formula specifically that you didn't
> even know you would need it again only until now

Use "up arrow" when running Lua in dialogue mode.

-- Martin