11 replies to this topic

[Kansas]

http://pastebin.com/MQY17TNh#

In lines 102 - 111, I'd like to get b == y to work but it just won't.

I've tried to debug it through making another script: http://pastebin.com/8JbmvhUy

..but it all comes up negative.

[LeonTheMisfit]

It looks like your problem is the way you're using variable y. The read() function returns a string and you want a number. You'll want to use Lua's tonumber() function to convert the input string to a number before using it in your loops. So you could do the following

for b = 1, tonumber(y) do
  --do stuff
end

Edited by LeonTheMisfit, 01 August 2014 - 11:25 PM.

[Kansas]

That is exactly it! Thanks a lot, I'm still new to programming

[LeonTheMisfit]

 Kansas, on 01 August 2014 - 11:34 PM, said:

That is exactly it! Thanks a lot, I'm still new to programming

No problem glad I could help! We were all new at some point.

[Inumel]

I know this is a bit late, but you could also do y = tonumber(read()), then just do b == y

[LeonTheMisfit]

And if you really want to make sure you're getting correct input you could do something like this

local y
repeat
  y = tonumber(read())
until y

tonumber returns nil if the given string isn't a valid number therefore this loop won't exit until a valid number is provided.

[Alice]

As has been said from other people,

repeat x until y

is a bad practice.
Instead,

local y
while true do
 term.write( "Number: " )
 y = tonumber( read() )
 if y then
  break
 end
end

[theoriginalbit]

 Alice, on 02 August 2014 - 07:02 AM, said:

As has been said from other people,

repeat x until y

is a bad practice.

who said it was bad practise? and why exactly did they say it was bad practice?

[Lyqyd]

Uh, no, if a repeat loop is the correct loop to use, use a repeat loop.

[LeonTheMisfit]

I'm curious to know who said this was a bad practice and what their reasoning was as well. From my understanding of how the repeat until loop works my example is perfectly acceptable, but I'm open to correction if a valid reason is provided. Also, in many of the languages I work with your example

 Alice, on 02 August 2014 - 07:02 AM, said:

local y
while true do
term.write( "Number: " )
y = tonumber( read() )
if y then
  break
end
end

would actually be considered a bad practice because it has hard to follow flow control, and while true loops are always discouraged even if a break is provided.

Edited by LeonTheMisfit, 02 August 2014 - 07:29 PM.

[Lyqyd]

No, while true loops aren't always discouraged. Again, use the right tool for the job.

[LeonTheMisfit]

 Lyqyd, on 02 August 2014 - 08:29 PM, said:

No, while true loops aren't always discouraged. Again, use the right tool for the job.

Okay to say they're always discouraged may have been the wrong way to put that. What I meant was that in many cases there is probably a better way, and one should only use it where it's necessary. Like you said, the right tool for the right job, and what I was really trying to get at is that this isn't one of the cases where it's at all the best way or necessary.

Edited by LeonTheMisfit, 02 August 2014 - 09:26 PM.