I added my whole solution code.

I've met a problem in Kata 'Take a Ten Minute Walk' - http://www.codewars.com/kata/take-a-ten-minute-walk/train/ruby

My code:

def isValidWalk(walk)
if walk.length!=10
return false
elsif
ns = 0
ew = 0
for i in 0..walk.length-1 do
if walk[i]=='n'
ns=ns+1
elsif walk[i]=='s'
ns=ns-1
elsif walk[i]=='e'
ew=ew+1
elsif walk[i]=='w'
ew=ew-1
end
i+=1
end

if ns==0 && ew==0
  return true
else
  return false
end

end
end

All tests passed correctly, but the system tells me about an Error:

STDERR:

main.rb:7: warning: found = in conditional, should be ==

But the string #7 is: for i in 0..walk.length-1 do
It does not contain symbol '='...

Is this a bug?