Array issues

Rails
1

Hey all,
When I do:
@posts = Post.find(:all)[0,5]
it gives me the first 5 posts

But when I do:
@posts = Post.find(:all)[10,20]
it gives me something like 20 posts or more, shouldn’t this give me only
10
post from 10 to 20?
what am I doing wrong?

thanx in advance

Pat

2

On Oct 15, 7:32 pm, “Patrick A.” [email protected] wrote:

thanx in advance

Pat

No, on an array it works like this…

array[offset, length]

So Post.find(:all)[10,20] will give you 20 posts starting at number 10.

_Kevin

3

But when I do:
@posts = Post.find(:all)[10,20]
it gives me something like 20 posts or more, shouldn’t this give me only
10
post from 10 to 20?
what am I doing wrong?

You want to use the range syntax, like arr[10…20]

4

On Oct 15, 2006, at 5:30 PM, _Kevin wrote:

post from 10 to 20?
what am I doing wrong?

No, on an array it works like this…

array[offset, length]

So Post.find(:all)[10,20] will give you 20 posts starting at number
10.

$ ri Array#[]
--------------------------------------------------------------- Array#[]
array[index] → obj or nil
array[start, length] → an_array or nil
array[range] → an_array or nil
array.slice(index) → obj or nil
array.slice(start, length) → an_array or nil
array.slice(range) → an_array or nil

  Element Reference---Returns the element at index, or returns a
  subarray starting at start and continuing for length elements, or
  returns a subarray specified by range. Negative indices count
  backward from the end of the array (-1 is the last element).
  Returns nil if the index (or starting index) are out of range.

     a = [ "a", "b", "c", "d", "e" ]
     a[2] +  a[0] + a[1]    #=> "cab"
     a[6]                   #=> nil
     a[1, 2]                #=> [ "b", "c" ]
     a[1..3]                #=> [ "b", "c", "d" ]
     a[4..7]                #=> [ "e" ]
     a[6..10]               #=> nil
     a[-3, 3]               #=> [ "c", "d", "e" ]
     # special cases
     a[5]                   #=> nil
     a[5, 1]                #=> []
     a[5..10]               #=> []

–
Eric H. - [email protected] - http://blog.segment7.net
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