What's wrong in my loop?

Ruby
1

I wrote the following loop some records ,

init an array db
get a record , loop on all records indexing by i
while record.start_at <= record.end_at
put in the db array [record.start_at, i]
end while
loop on records
end

but it seems that’s Ruby doesn’t like it … what’s wrong ? is theer any
way to write it better ?

  db = []
 record.each do |b|
    aDate = b.start_at
    i = 0
    while aDate <= b.end_at
      db << [ aDate, i ]
      i++
      aDate= aDate + i
    end
  end

jossss

2

I think you might find it’s the “i++”.

Try “i.next” or “i += 1”

t.

3

Hi Josselin,

Tom is right about the “i++”.

Also, it doesn’t look like your pseudo-code matches your ruby code
functionality.

I’ll give it a shot as what you may want to do, just a guess…

db = []
record.each do |b|
(b.end_at - b.start_at).times { |i| db << [b.start_at+i, i ] }
end

4

On 2006-10-02 14:54:58 +0200, Stephane E. [email protected]
said:

record.each do |b|
(b.end_at - b.start_at).times { |i| db << [b.start_at+i, i ] }
end

thansk Tom & Steph
newbie I am mixin any languages into it…
I actually need to remember first that Ruby is OO, so i.next makes more
sense compared to i++

joss

5

On 10/2/06, Josselin [email protected] wrote:

db = []
record.each do |b|
(b.end_at - b.start_at).times { |i| db << [b.start_at+i, i ] }
end

thansk Tom & Steph
newbie I am mixin any languages into it…
I actually need to remember first that Ruby is OO, so i.next makes more
sense compared to i++

The expression i++ isn’t valid ruby.

Keep in mind that

i.next

all by itself has no effect on i:

i = 2
p i.next => 3
p i => 2

Don’t confuse the variable i with the object it contains. The
expression i++ simply asks the object 2 for it’s successor leaving it
unchanged.

i += 1

which is the same as:

i = i + 1

computes the value of i + 1 and assigns the result to the variable i.

you could also use

i = i.next

–
Rick DeNatale

My blog on Ruby
http://talklikeaduck.denhaven2.com/