Bug #9081: Unexpected result for and opreator

• Status: Rejected
• Assignee: -
• Target version: -
• ruby -v: ruby 2.0.0p247 (2013-06-27 revision 41674) [x86_64-darwin11.4.2]
• Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN

[aminhotob (Mo Amin)]

I use this code to test and confirm this result

def show
@profile = .......
puts "=================="
puts user_signed_in?
puts current_user.id
puts @profile.user.id
puts user_signed_in? and (current_user.id == @profile.user.id)
puts true and (1 == 2)
puts true and false
puts true && false
puts "=================="
.......
end

this is console output

==================
User Load (0.6ms) SELECT users.* FROM users WHERE users.id = 3 ORDER BY users.id ASC LIMIT 1
true
3
User Load (0.4ms) SELECT users.* FROM users WHERE users.id = 11 ORDER BY users.id ASC LIMIT 1
11
true
true
true
false

the last two lines will clear the problem, I except and, && is the same !

ruby -v ruby 2.0.0p247 (2013-06-27 revision 41674) [x86_64-darwin11.4.2]
rails -v Rails 4.0.0

[gergoerdosi (Gergo Erdosi)]

This isn't unexpected behavior. (({and})) and (({or})) are not boolean, but control flow operators. Execution stops when an operation returns (({nil})) or (({false})). Use (({&&})) or (({||})) for the desired behavior.

• Status changed from Open to Rejected
• Priority changed from 5 to Normal

This isn't a bug. The 'and' operator has lower precedence than '&&', so when you write this code:

puts true and false

It's parsed as:

puts(true) && false

If you instead write:

puts true && false

Then Ruby will parse this expression like this, as you intend:

puts(true && false)