Re: Documenting Lua gotchas for newbies.

[HyperHacker <hyperhacker@...>]

On Wed, Dec 8, 2010 at 02:44, Kristofer Karlsson
<kristofer.karlsson@gmail.com> wrote:
> It's mostly a badly designed api function, where the meaning of one argument
> completely changes if you add another argument.
> Imo, it should be:
> table.insert(t, value [, position])
> or even better, split table.insert into table.append(t, value) and
> table.insert(t, position, value)
>
>
> On Wed, Dec 8, 2010 at 10:27 AM, Dirk Laurie <dpl@sun.ac.za> wrote:
>>
>> Here is a function that reads up to 10 numbers from a line:
>>
>> function setup(line)
>>    local data = {}
>>    while #data<10 do
>>        for w in line:gmatch("[^%s]+") do
>>            table.insert(data,(assert(tonumber(w),"Error")))
>>        for k=1,#data do print(k,data[k]) end
>>        break
>>        end
>>    end
>>
>> E.g.
>> > setup("2 2 4 4 0 6 0 0")
>> 1   2
>> 2   2
>> 3   4
>> 4   4
>> 5   0
>> 6   6
>> 7   0
>> 8   0
>>
>> Now, small change, remove the parentheses around the assertion.
>>
>>            table.insert(data,assert(tonumber(w),"Error"))
>>
>> Guess what happens before trying it!
>>
>> Is this a newbie gotcha?
>>
>> Dirk
>>
>>
>
>

I've often found myself writing table.append instead of table.insert
and ultimately decided to make it an alias for readability's sake.

-- 
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