Examine individual changes

''''QX''' is a minimal language made by [[User:↑]].[[User:↑|why is there a filter rule]] [[File:QX logo.png|thumb|alt=QX logo|Logo.]] == Commands == {| class="wikitable" |- ! Command !! What it does |- | Q [a] || Increments the current value at pointer by a. Can decrement if a is negative |- | X [a] [b] || If a <= previous item at pointer then go to previous item at pointer and jump to line b else go to next item at pointer. |} == Computational class == QX is [[Turing-complete]] by translation from unbounded [[brainfuck]]. {| class="wikitable" ! Command ! Translation |- | <code>+</code> | <code>Q 1</code> |- | <code>-</code> | <code>Q -1</code> |- | <code>&gt;</code> | <code>X ∞ 0</code> |- | <code>&lt;</code> | <code>X -∞ n</code>, where <code>n</code> is the next command |- | <code>[</code> and <code>]</code> | <code>X ∞ 0 X 1 s X -∞ e1 X -∞ e2</code>, where <code>s</code> is after the corresponding <code>[</code>, <code>e1</code> is <code>X -∞ e2</code>, and <code>e2</code> is after the corresponding <code>]</code> |} Note that this assumes infinity is a valid constant. A translation from bounded brainfuck will avoid infinity: {| class="wikitable" ! Command ! Translation |- | <code>+</code> | <code>Q 1 X 257 0 X 256 d X 0 n1 X 0 n2 Q -256</code>, where <code>d</code> is <code>Q -256</code>, <code>n1</code> is <code>X 0 n2</code>, and <code>n2</code> is the next command |- | <code>-</code> | <code>Q -1 X 255 0 X 0 n X -1 d1 X -1 d2 Q 256</code>, where <code>n</code> is the next command, <code>d1</code> is <code>X -1 d2</code> and <code>d2</code> is <code>Q 256</code>. |- | <code>&gt;</code> | <code>X 256 0</code> |- | <code>&lt;</code> | <code>X 0 n</code>, where <code>n</code> is the next command |- | <code>[</code> and <code>]</code> | <code>X 256 0 X 1 s X 0 e1 X 0 e2</code>, where <code>s</code> is after the corresponding <code>[</code>, <code>e1</code> is <code>X 0 e2</code>, and <code>e2</code> is after the corresponding <code>]</code> |} There is also a translation from [[Brainpocalypse]]: {| class="wikitable" |- ! Brainpocalypse !! QX |- | {{cd|<}} || {{cd|X 0 n}} where n is next line |- | {{cd|>}} || {{cd|X ∞ 0}} where lim is the absolute limit of the numbers |- | {{cd|+}} || {{cd|Q 1}} |- | {{cd|-}} || {{cd|X ∞ 0 X 1 d X -1 s X -1 1 Q -1}}, where line <code>d</code> is <code>Q -1</code> and line <code>s</code> is <code>X -1 1</code> |} == Examples == === [[Infinite loop]] === X 0 1 === [[A+B Problem]] === Q ? Q ? If A and B must start separate: Q ? X 1 0 Q ? X 1 6 X 0 12 Q -1 X 1 0 Q 1 X ∞ 0 X 0 4 [[Category:Languages]] [[Category:2025]] == Lua interpreter == Made by [[User:Aadenboy]] <pre> assert(arg[1], "Argument 1 must be a file to interpret") local file = io.open(arg[1], "r") assert(file, "File not found") local code = file:read("*a") file:close() local range = {1, 1} local mem = {0} local pointer = 1 local commands = {} code = code:gsub("∞", "i") for pos, qx, a, b in code:gmatch("()([QX])%s*([%d%-%?%.i]*)%s*([%d%-%?%.i]*)") do a = a == "?" and "?" or (a == "i" and math.huge or (a == "-i" and -math.huge or tonumber(a))) b = b == "?" and "?" or (b == "i" and math.huge or (a == "-i" and -math.huge or tonumber(b))) local line = ({code:sub(0, pos):gsub("\n", "")})[2] + 1 local char = #code:sub(0, pos):match("\n?([^\n]+)$") assert(a, line..":"..char..": "..qx.." expects at least one integer") assert(qx == "Q" or b, line..":"..char..": X expects two integers") table.insert(commands, {qx = qx, a = a, b = qx == "X" and b}) end local i = 1 local steps = 0 repeat steps = steps + 1 local c = commands[i] local a = c.a == "?" and (tonumber(io.read()) or 0) or c.a local b = c.b == "?" and (tonumber(io.read()) or 0) or c.b if c.qx == "Q" then i = i + 1 mem[pointer] = mem[pointer] + a else local pre = mem[pointer-1] or 0 pointer = pointer + (a <= pre and -1 or 1) mem[pointer] = mem[pointer] or 0 i = a <= pre and b or i + 1 end range = {math.min(range[1], pointer), math.max(range[2], pointer)} until i < 1 or i > #commands or steps >= (tonumber(arg[2]) or math.huge) print(steps.." steps\nPointer at "..pointer.."\nMemory:") for i=range[1], range[2] do print("\t["..i.."]: "..mem[i]) end </pre> [[Category:Implemented]][[Category:Turing tarpits]][[Category:Turing complete]]'