Lua associative arrays

[geocine]

I have this code.

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local colors = {
		red = { r = 255,g = 0,b = 0 },
		green = { r = 0,g = 128,b = 0 },
		blue = { r = 0,g = 0,b = 255},
	}

Why can't I access this using indices? Am I doing something wrong?

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colors[1].r

I could access it through indices using this declaration

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local colors = {
		{ r = 255,g = 0,b = 0 },
		{ r = 0,g = 128,b = 0 },
		{ r = 0,g = 0,b = 255},
	}

However I would like to be able to access it using

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colors[1].r
-- and
color.red.r

[dreadkillz]

Lua's table contains two parts: The hash and the array. Your first table contains keys in the hash part, (red,green,blue keys). If you want to access your values with numbered indices You'll have to add your value to the array part as well.

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t[key] = value
t[1] = value

This is kinda silly though as you have duplicate values for no reason. If you're planning on iterating through your table in a certain order, I recommend storing your values with indices.

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for i = 1,#t do
... -- do stuff with t
end

[Robin]

You could do:

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local colors = {
      { r = 255,g = 0,b = 0 },
      { r = 0,g = 128,b = 0 },
      { r = 0,g = 0,b = 255},
   }

local color_names = {'red', 'green', 'blue'}

for i = 1, #colors do
    colors[color_names[i]] = colors[i]
end