See if a space-seperated code in a string matches any object in a table Lua

Question

I have a string which is a space-seperated sequence of codes such as "O R LE Pdc". The code needs to check if a code matches any object in a table (such as {"R", "BE", "Cre"}) return true, if not, return false. Here, it would return true because "R" exists.

I am completely stumped and do not know how to solve this problem.

score 2 · Accepted Answer · answered Jul 01 '22 at 14:26

-- the table you're searching through
local t = {"R", "BE", "Cre"}
-- the text you're searching for
local txt = "O R LE Pdc"

-- now create a look-up table
local lut = {}
for _,v in ipairs(t) do
  lut[v] = true
end

-- for every "word" in your string, check if you find it in the look up table
for str in txt:gmatch("%w+") do
  if lut[str] then print("found it") end
end

Alternatively:

for _,v in ipairs(t) do
   if txt:find(v) then print("found it") end
end

Or

for _, v in ipairs(t) do
  for w in txt:gsub("%w+") do
    if v == w then print("found it") end
  end
end

There are many other ways. Which one to choose will depend on the amount of data you're processing.

See if a space-seperated code in a string matches any object in a table Lua

1 Answers1