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What's the point of 'do' outside of a loop?
I took a peek at Stravant/StickMasterLuke's TweenCFModule, and found that much of the mid-section of the code was encapsulated by a do - end. What's the point? Organization? Thanks for any help! :)
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5
Part of it is organization, but the technical reason for it is that Lua uses do ... end to define generic 'blocks' of code. while and for loops use these inherently, although I'm not sure about the bytecode for repeat loops and if statements.
The consequence of this is that do ... end blocks create a layer of scope:
1 | x = 5 |
2 | do |
3 | local x = 15 |
4 | print(x) --> 15 |
5 | end |
6 | print(x) --> 5 |
And any other consequences you can draw from that. It's useful of you want to reuse variable names, although it's more useful to deny access to variables declared in the global scope of a script:
01 | local board = Instance.new("BillboardGui", workspace.Player.Head) |
02 | board.Name = "Test" |
03 | do |
04 | local f = Instance.new("Frame", board) |
05 | f.Name = "Example" |
06 | f.Size = UDim2.new(1,0,1,0) |
07 | f.BackgroundColor3 = Color3.new() |
08 | f.BackgroundTransparency = .5 |
09 | f.BorderSizePixel = 0 |
10 |
11 | local txt = Instance.new("TextLabel", f) |
12 | --I think you get the idea. |
13 | end |
14 |
15 | print(board) --Test |
16 | print(f) --nil |
17 | print(txt) --nil |
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"The consequence of this is that do ... end blocks create a layer of scope:" Upvoted Validark 1580 — 9y
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I've never actually known this till now. Upvoted! Spongocardo 1991 — 9y
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Thanks so much, extremely helpful! saenae 318 — 9y