return {

showIntImpl = (function(n) return tostring(n) end),

showNumberImpl = (function(n)

-- Match PureScript `show`: NaN/Infinity spellings (Lua prints inf/nan),

-- and integral Numbers keep a trailing ".0" so they round-trip as Number.

if n ~= n then return "NaN" end

if n == math.huge then return "Infinity" end

if n == -math.huge then return "-Infinity" end

local str = tostring(n)

if str:find("[.eE]") then return str end

return str .. ".0"

end),

showCharImpl = (function(n)

local code = n:byte()

if code < 0x20 or code == 0x7F then

if n == "\a" then return "'\\a'" end

if n == "\b" then return "'\\b'" end

if n == "\f" then return "'\\f'" end

if n == "\n" then return "'\\n'" end

if n == "\r" then return "'\\r'" end

if n == "\t" then return "'\\t'" end

if n == "\v" then return "'\\v'" end

return "'\\" .. tostring(code) .. "'"

end

if n == "'" or n == "\\" then return "'\\" .. n .. "'" end

return "'" .. n .. "'"

end),

showStringImpl = (function(s)

-- Mirror PureScript's `show`: wrap in double quotes and escape control

-- characters, '"' and '\' so the result round-trips to a String literal.

local out = {"\""}

local len = #s

local i = 1

while i <= len do

local c = s:sub(i, i)

local b = c:byte()

if c == "\"" or c == "\\" then

out[#out + 1] = "\\" .. c

elseif b == 0x07 then

out[#out + 1] = "\\a"

elseif b == 0x08 then

out[#out + 1] = "\\b"

elseif b == 0x0C then

out[#out + 1] = "\\f"

elseif b == 0x0A then

out[#out + 1] = "\\n"

elseif b == 0x0D then

out[#out + 1] = "\\r"

elseif b == 0x09 then

out[#out + 1] = "\\t"

elseif b == 0x0B then

out[#out + 1] = "\\v"

elseif b < 0x20 or b == 0x7F then

-- numeric escape; "\&" guards against a following digit being

-- swallowed into the escape (e.g. "\27\&5" /= "\275").

local nxt = s:sub(i + 1, i + 1)

local gap = (nxt >= "0" and nxt <= "9") and "\\&" or ""

out[#out + 1] = "\\" .. tostring(b) .. gap

else

out[#out + 1] = c

end

i = i + 1

end

out[#out + 1] = "\""

return table.concat(out)

end),

showArrayImpl = (function(f)

return function(xs)

local l = #xs

local ss = {}

for i = 1, l do ss[i] = f(xs[i]) end

return "[" .. table.concat(ss, ",") .. "]"

end

end)

}