How can I write this is rails (for loop)

Rails
1

I want to write this in rails:

@aux= @rep_tickets.rp_parts.size

for i=0, i< @aux, i++
@[email protected] + @rep_tickets.rp_part[i].price
end

2

John S. wrote:

I want to write this in rails:

@aux= @rep_tickets.rp_parts.size

for i=0, i< @aux, i++
@[email protected] + @rep_tickets.rp_part[i].price
end

@rep.ticket.price = @rep_tickets…rp_parts.map(:&price).sum

3

Russell McConnachie wrote:

@rep.ticket.price = @rep_tickets…rp_parts.map(:&price).sum

Wow, fat fingered that.

@rep.ticket.price = @rep_tickets.rp_parts.map(&:price).sum

4

Russell McConnachie wrote:

Russell McConnachie wrote:

@rep.ticket.price = @rep_tickets…rp_parts.map(:&price).sum

Wow, fat fingered that.

@rep.ticket.price = @rep_tickets.rp_parts.map(&:price).sum

Doesn’t seem to work:

@repair_ticket.total_price = @repair_ticket.rp_parts.map(:&price).sum
SyntaxError: compile error
(irb):71: syntax error, unexpected tIDENTIFIER, expecting ‘)’
@repair_ticket.total_price = @repair_ticket.rp_parts.map(:&price).sum

5

Frederick C. wrote:

On 10 Jan 2008, at 18:23, Russell McConnachie wrote:

@rep.ticket.price = @rep_tickets…rp_parts.map(:&price).sum

or even @rep_tickets.rp_parts.sum(:&price)

(consider also @rep_tickets.rp_parts.target.sum(:&price)
The difference between the two is that the first will always hit the
database (ie it will do select sum(price) from …) whereas the second
won’t if rp_parts has already been loaded (assuming rp_parts is an
active record association)

Fred

Does not work!
Repair tickets and rp_parts are HABTM. Help!

6

On 10 Jan 2008, at 18:23, Russell McConnachie wrote:

@rep.ticket.price = @rep_tickets…rp_parts.map(:&price).sum

or even @rep_tickets.rp_parts.sum(:&price)

(consider also @rep_tickets.rp_parts.target.sum(:&price)
The difference between the two is that the first will always hit the
database (ie it will do select sum(price) from …) whereas the second
won’t if rp_parts has already been loaded (assuming rp_parts is an
active record association)

Fred

7

On Jan 10, 2008, at 1:34 PM, John S. wrote:

@repair_ticket.total_price =
@repair_ticket.rp_parts.map(:&price).sum
SyntaxError: compile error
(irb):71: syntax error, unexpected tIDENTIFIER, expecting ‘)’
@repair_ticket.total_price = @repair_ticket.rp_parts.map(:&price).sum

.map(&:price)

Note that & causes the following object, if not already a Proc, to be
sent a .to_proc method. Rails defines Symbol#to_proc. Your syntax
error is because you have transposed the & and : in the line.

-Rob

Rob B. http://agileconsultingllc.com
[email protected]