[Fixed] Adding data: to game

[Rafiz]

There's part of code in my mod : https://pastebin.com/8j7sGeA4 (whole file : https://pastebin.com/Sw9V7nzk)

In this part of code I define technology and add it to game. But it is nowhere to be found, I just ... don't have it in game.
Here's log from game : https://pastebin.com/cWfQiLjR my mod loads (0.741), have no errors, it is enabled... I don't understand what is failing here.

What am I doing wrong? I'm pretty sure this exact mod worked, but I worked on it like half year ago, so few new versions of game came out.

I changed value of property : order = ~~~ to some other, so it is not exactly same as in vanilla techs, but it did nothing, I have no ideas on what can I try to do.

[Rafiz]

Typo!
data:extend(
{
recile_lube,
should be recipe_lube.
That's strange that nothing crashed. I guess data:extend just accepts nil and ends adding elements from table once it gots to nil. I would rather expect it to ... if not crash everything, then at least continue checking next elements.
Data:extend shouldn't be looping past array, until value under current index returns nil (IMO). It should rather just check # of elements in array and iterate over # elements. Maybe it does that, I don't know. It just looks as if it was "end-of-array being nil" based.

[robot256]

In Lua, nil entries in a table/array are simply not stored at all.

a=nil
tab={a}

Is the same as

tab={nil}

Is the same as

tab={}

In all cases #tab=0

The only time it matters is array spacing:

tab={nil,nil,nil,42}

Is the same as

tab={[4]=42}

And #tab=4 but table_size(tab)=1 (iirc)

[FuryoftheStars]

Well, that’s the thing the OP was confused about in their 2nd post.

If I’m following that post correctly, they were essentially entering this:
data:extend({nil, dat2, dat3, …})
And the game wasn’t inputting any of it.

[Silari]

Probably because of how array's are handled in LUA and where certain functions consider their end to be.

The basic Lua library provides ipairs, a handy function that allows you to iterate over the elements of an array, following the convention that the array ends at its first nil element.

So in this case, data:extend expects an array, finds the first entry to be nil, and thus treats the array as if it were empty. data:extend uses ipairs to iterate the data given to it, per the code at https://github.com/wube/factorio-data/b ... loader.lua . There's also a check that the table isn't empty, but since that uses the # operator I believe it's missing this case - the table isn't empty, it's just not being fully iterated over.