Display table contents in lua

Question

What I'm trying to do is display the contents of a table using the following code in Lua.

local people = {
   {
   name = "Fred",
   address = "16 Long Street",
   phone = "123456"
   },

   {
   name = "Wilma",
   address = "16 Long Street",
   phone = "123456"
   },

   {
   name = "Barney",
   address = "17 Long Street",
   phone = "123457"
   }

}
for k, v in pairs(people ) do
    print(k, v)
end

The result obtained:

1   table: 0x9a2d8b0
2   table: 0x9a2d110
3   table: 0x9a2cb28

Answer 1

To display nested tables, you will need to use nested loops.

Also use ipairsto iterate over tables like an array, and pairsto iterate over tables like an entry.

local people = {
   {
       name = "Fred",
       address = "16 Long Street",
       phone = "123456"
   },
   {
       name = "Wilma",
       address = "16 Long Street",
       phone = "123456"
   },
   {
       name = "Barney",
       address = "17 Long Street",
       phone = "123457"
   }
}

for index, data in ipairs(people) do
    print(index)

    for key, value in pairs(data) do
        print('\t', key, value)
    end
end

Conclusion:

1   
        phone   123456          
        name    Fred            
        address 16 Long Street          
2   
        phone   123456          
        name    Wilma           
        address 16 Long Street          
3   
        phone   123457          
        name    Barney          
        address 17 Long Street  

Answer 2

This recursively serializes the table. A variant of this code can be used to generate JSON from the table.

function tprint (tbl, indent)
  if not indent then indent = 0 end
  local toprint = string.rep(" ", indent) .. "{\r\n"
  indent = indent + 2 
  for k, v in pairs(tbl) do
    toprint = toprint .. string.rep(" ", indent)
    if (type(k) == "number") then
      toprint = toprint .. "[" .. k .. "] = "
    elseif (type(k) == "string") then
      toprint = toprint  .. k ..  "= "   
    end
    if (type(v) == "number") then
      toprint = toprint .. v .. ",\r\n"
    elseif (type(v) == "string") then
      toprint = toprint .. "\"" .. v .. "\",\r\n"
    elseif (type(v) == "table") then
      toprint = toprint .. tprint(v, indent + 2) .. ",\r\n"
    else
      toprint = toprint .. "\"" .. tostring(v) .. "\",\r\n"
    end
  end
  toprint = toprint .. string.rep(" ", indent-2) .. "}"
  return toprint
end

execute your table:

 local people = {
   {
   name = "Fred",
   address = "16 Long Street",
   phone = "123456"
   },

   {
   name = "Wilma",
   address = "16 Long Street",
   phone = "123456"
   },

   {
   name = "Barney",
   address = "17 Long Street",
   phone = "123457"
   }

}


print (tprint(people))

generates this:

  {
  [1] =     {
      name= "Fred",
      phone= "123456",
      address= "16 Long Street",
    },
  [2] =     {
      name= "Wilma",
      phone= "123456",
      address= "16 Long Street",
    },
  [3] =     {
      name= "Barney",
      phone= "123457",
      address= "17 Long Street",
    },
}

Answer 3

, :

for i,t in ipairs(people) do
  print('Record',i)
  print('Name',t.name)
  print('Address',t.address)
  print('Phone',t.phone)
  print()
end