Replace String Characters by Index in Lua

Question

If you've every played hangman, you will readily understand what I'm trying to accomplish. All I want is to replace characters at certain indices with other characters. Here's what I'm currently doing:

word = getwordoflength(10)
found = string.rep("_", 10)

while found ~= word do

  char = getcharfromuser()

  temp = ""
  for i = 1, 10 do
    if word:sub(i, i) == char then
      temp = temp..char
    else
      temp = temp..found:sub(i, i)
    end
  end
  found = temp
end

Now, to me this seems inordinately stupid and inefficient, but maybe there is no better way. Bottom line, what's the 'right' way to do this?

Egor Skriptunoff Egor Skriptunoff · Accepted Answer · 2014-07-24T23:25:42

while found ~= word do
   local char = getcharfromuser()
   for i in word:gmatch('()'..char) do
      found = found:sub(1,i-1)..char..found:sub(i+1)
   end
end

One more way:

while found ~= word do
   local char = getcharfromuser()
   for i in word:gmatch('()'..char) do
      found = found:gsub('().', {[i]=char})
   end
end

Replace String Characters by Index in Lua

1 Answers