(0,3),u,r,u,l,u #True

(0,3),u,r,u,l,u #True

(0,3),u,r,u,l u #False because of space b/w l and u

if !misc_text.match(/^(d+,d+)(,[udlr])+)/)

def check_it(s)
  (s.chars.chunk {|c| c =~ /[urld]/}.to_a.size == s.count('urld') &&
    s =~ /^[(),durld]*$/) ? true : false
end

check_it('(0,3),u,r,u,l,u') #=> true
check_it('(0,3),u,r,u,l u') #=> false
check_it('(0,3),u,r,u,lu')  #=> false

s = '(0,3),u,r,u,lu'

a = s.chars.chunk {|c| c =~ /[urld]/}.to_a
  #=> [[0, ["u"]], [0, ["r"]], [0, ["u"]], [0, ["l", "u"]]]

a.size #=> 4

s.count('urld') #=> 5

s = '(0,3),u,r,u,l u'

s.chars.chunk {|c| c =~ /[urld]/}.to_a.size
  #=> a = [[0, ["u"]], [0, ["r"]], [0, ["u"]], [0, ["l"]], [0, ["u"]]]
  #   a.size => 5
  #   5 == s.count('urld') => true

s =~ /^[(),durld]*$/ #=> nil

class String
   def catch str
      str.split('').all? {|l| /,#{l}(,|b)/ =~ self }
   end
end

"(0,3),u,r,u,l,d".catch('ulrd') # => true

"(0,3),u,r,u,l d".catch('ulrd') # => false