Learn Lua in Neovim: Table References vs Copies — The Copy Trap, Shallow & Deep Copy | Episode 22

Assigning a table to a new variable doesn't copy it — both names point to the same data. In this episode we uncover the copy trap, show why changes through one variable affect the other, build a shallow_copy function, and then build a recursive deep_copy for nested tables. Every keystroke is shown on screen with 3-second pauses so you can follow along at your own pace. What You'll Learn: - Tables are references — assignment shares, not copies - The copy trap — modifying one variable changes both - shallow_copy(t) — loop and copy top-level keys - Shallow copy limitation — nested tables are still shared - deep_copy(t) — recursive function that copies all levels - When to use shallow vs deep copy Neovim Commands Used: - * — search the word under the cursor - n — jump to next search match - yy — yank (copy) the current line - p — paste below - :s/old/new/g — substitute on the current line Timestamps: 0:00 Intro 0:12 Preview 0:44 Open file 1:07 The Reference Trap — local b = a 2:07 Run — both a and b are 99 3:11 Shallow Copy function 4:42 Test shallow copy — c and d independent 5:38 Run shallow copy 6:04 Shallow Copy Trap — nested tables shared 7:09 Run — e.scores changed too! 8:16 Deep Copy — recursive solution 10:16 Test deep copy with yy/p/:s 11:58 Run — fully independent 12:29 Review — * search variable, n next match 12:47 Recap 13:19 Next: The Math and String Libraries Practice code: https://github.com/GoCelesteAI/learn-lua-in-neovim This is Episode 22 of the Learn Lua in Neovim series. New episodes cover libraries, metatables, OOP, and more — all coded inside Neovim. Taught by CelesteAI. Like & subscribe for more tutorials! #lua #neovim #programming #tutorial #beginners #learnlua #luaprogramming #neovimtutorial #luareferences #luacopy #coding Tags lua, lua tutorial, learn lua, lua table references, lua copy trap, lua shallow copy, lua deep copy, lua table assignment, lua reference vs copy, lua recursive copy, lua clone table, lua tables, lua for beginners, neovim lua, neovim tutorial, learn lua in neovim, lua episode 22, programming tutorial, coding tutorial, beginner programming, lua 2026, neovim 2026, screenkey, code along, lua basics, lua data structures