How to check if a string begins with prefix and contains specific keyword in Ruby-CodePudding

I am trying to find an efficient way of doing this. A function to return True if the entry string has a Ph.D/Medical Doctor ( which means prefix of 'Dr.') and the entry has name 'Alex' in it.

I tried the below code which works, but I think there should be a more efficient way of doing it. I will appreciate any thoughts.

str1 = "Dr. Moses Alex"
str2 = "Dr. Ben Mora"

def match st
  if st.include?('Dr.') and st.include?('Alex')
    return true
  else 
   return false
 end
end

match(str1) # true
match(str2) # false

CodePudding user response：

Your code could be simplified to:

def match(string)
  string.start_with?('Dr.') && string.include?('Alex')  
end

This works because a method in Ruby always implicitly returns the value returned by the last statement. Therefore there is no need for explicit returns.

CodePudding user response：

The code looks good. The only feedback I have is regarding the use of 'include?' function for the prefix. Try to use 'start_with?' function instead, so that you don't get True even when the the "Dr" is within the string.

def match st
  if st.start_with?('Dr.') and st.include?('Alex')  
    return true
  else 
    return false
  end
end

CodePudding user response：

I would use String#match? with a simple regular expression:

r = /\ADr\.. \bAlex\b/

"Dr. J. Alex Knowitall".match?(r) #=> true
"He's Dr. J. Alex Knowitall".match?(r) #=> false
"Dr. J. Alexander Knowitall".match?(r) #=> false

We can write the regular expression in free-spacing mode to make it self-documenting:

r =
/
\A    # match beginning of string
Dr\.  # match literal "Dr."
.     # match one or more characters, as many as
      # possible, other than line terminators
\b    # match a word boundary
Alex  # match literal "Alex"
\b    # match a word boundary
/x    # assert free-spacing regex definition mode

With any solution some strings, if permitted, may cause problems, an example being, "Dr. Bubba Knowitall and Alex are brothers".