JornAggror Blog

You probably know this already, but another way is to use pairs() to iterate through all pairs in the table, or ipairs() to iterate through them in numerical order.

13 minutes ago, Josh said:

or ipairs() to iterate through them in numerical order.

You have the same issue there when using ipair, the 0 index is ignored. Try it out Lua online.

output

create enemies: 4
I am enemy 0
I am enemy 1
I am enemy 2
I am enemy 3

#enemiesCount: 3    

I am enemy 0
I am enemy 1
I am enemy 2

Using IPAIR
1_I am enemy 1
2_I am enemy 2
3_I am enemy 3

Using PAIR
1_I am enemy 1
2_I am enemy 2
3_I am enemy 3
0_I am enemy 0

 

I usually avoid indices at all. Instead, I insert items with Table.Insert() and iterate through them with pairs() or ipairs():

--Create a new table
mytable={}

--Insert some items into the table
table.insert(mytable,"Thing 1")
table.insert(mytable,"Thing 2")
table.insert(mytable,"Thing 3")

 

2 minutes ago, Josh said:

I usually avoid indices at all. Instead, I insert items with Table.Insert() and iterate through them with pairs() or ipairs():

I guess for general tables that is a better approach. However when using a multidimensional array, I prefer indices.  I do find the Table.insert function a bit weird. I wish Lua did it more like below. It helps when using intelisense.

myTable:Insert("Thing 1") 

 

I think it would actually work if you made mytable.insert equal to the function table.insert. ?

Yep, it works:

local enemies = {}
local enemyCount = 4

enemies.insert = table.insert

print("create enemies: " .. enemyCount )
for i = 1, enemyCount do
   enemies:insert("I am enemy " .. i)                 
end

print("\nUsing IPAIR")
for key,value in ipairs(enemies) do
  print(key .. "_" .. value)                  
end

print("\nUsing PAIR")
for key,value in pairs(enemies) do
  if type(value)=="string" then
    print(key .. "_" .. value)                  
  end
end

 

13 hours ago, Josh said:

I think it would actually work if you made mytable.insert equal to the function table.insert. ?

That flexibility is the strong part of Lua (arguably also a weakness). I am sure you could even adept the default table behavior to do this automatically for all tables. It is a pity Lua doesn't do this by default.

Well, notice above I had to add a type check because now one of the field of the table is a function. So you would probably not want this by default.

You could probably use a metamethod to hide the function from the pairs() iterator.