[0.5.0]comparison to values extracted from a file

[rhezalouis]

hi, nice to meet all of you. [has this been a proper introduction?]

i put flexible key assignment to a program by putting the key values on a text file and extract them into a table tKey using the code below:

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tKey = ()
function tKey.fLoad()
    counter = 0;
    for vLine in love.filesystem.lines(tMacro.keyfileName) do
        if string.find(vLine, "><", 1 , 1) == 1 then break; end -- end of file indicator, don't read
        if string.find(vLine, "--", 1 , 1) == nil then           -- not a comment
            tKey[counter] = vLine;
            counter = counter + 1;
        end
    end
end

the function tKey.fLoad() is called at callback load() and the table tKey is used in the callback keypressed(key):

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function keypressed(key)
    if (key == tKey[0]) or (key == tKey[1]) then
        fNextState(); --go to the next program state
    end
end

the expression (key == tKey[0]) is not working. could anyone provide me a way to put the extracted value on an expression?

notes: i have read a previous post about "User Define keys in a game" http://love2d.org/forum/viewtopic.php?f ... 02&start=0; please note that my question is not about the user-defined keys but on how to put the extracted values in an expression [is it possible without using complicated loadstring() or am i thinking in a too complicated way?].

thank you for your time.

[Robin]

I suppose the strings that are extracted are "left", "right", "a", "0", "space" and things like that.
If so, it's rather simple. Constants are directly in the love table, and key constants are prefixed by key_:

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love.key_left

Which means this should work:

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tKey[counter] = love["key_"..vLine] -- works since t.hi == t["hi"]

[kikito]

Howdy!

What are the values of tKey[0] and tKey[1]? Can you print them somewhere? print('tKey[0]: [' .. tKey[0] .. ']') will show them on the log.

Also, have you thought about coding your settings directly in a lua file?. Your file could be called "tKey.lua", and look like this:

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  tKey = { 'a', 'b' }

This will make tKey[0] = 'a' and tKey[1] = 'b' after you invoke this:

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  doFile('tKey.lua')

Which in my opinion is as simple as it can get.

Or even better, give the keys a proper name instead of 0s and 1s:

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  tKey = { fire = 'a', jump = 'b' }

Now tKey.fire = 'a' and tKey.jump='b'. You can then do:

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function keypressed(key)
    if (key == tKey.jump) then
        fNextState(); --go to the next program state
    end
    if (key == tKey.fire) then
        fThrowAFireball(); -- or something else
    end
end

[rhezalouis]

howdy!

ah, sorry, i forgot to mention the values in the file. i use this keyList.txt [the quotes are experimental]:

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--
love.key_return
"love.key_space"
><

and the extraction returns these values correctly, so that the variable printing yields:

• tKey[0] = love.key_return
• tKey[1] = "love.key_space"

throwing the whole name would cease it from being a key constant from the table love[]. my code seems to cause the assignments to be:

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tKey[0] = "love.key_return"
tKey[1] = "\"love.key_space\""

• @robin: huaaa, i did not notice that the constant is a table under the name "love". i thank you very much. you are right, i have changed the text file to:

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  --
  return
  space
  ><

  and uses your

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  tKey[counter] = love["key_"..vLine];

  so that the assignment is correct:

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  tKey[0] = love["key_return"]
  --or
  tKey[1] = love.key_space

  and the comparison works fine. these chunks are quite tricky, aren't they?
  i thought using this modular-list scheme would simplify modification of the programme. do you think that this external file would ease the saving process or something else?
• @kikito: thank you so much for your kind response.
  i have put these keys in a separate file; but it is formatted as a list of keys, so that no lua is required in that file. i'll try to name the indexes of the key using another LÖVE-LuaStringScript combo. that's a good advice.