From: Benedikt Heinen <ruby@...>
Date: 2005-11-17T21:15:20+09:00
Subject: Re: extracting lines from an address

>> I have an address stored in mysql as a text field.
>> I'm using ActiveRecord to access the field.
>> But how do I get each line of the address in to their own strings?

>> Address = "12, HouseName
>>            Street
>>            City
>>            Country"
>>
>> Address_line1 = "12, HouseName"
>> Address_line2 = "Street"
>> Address_line3 = "City"
>> Address_line4 = "Country"
>
> address = "12, HouseName
>           Street
>           City
>           Country"
>
> address_lines = address.split( /\n\s*/ )
>
> puts address_lines[0]
>
> address_line1, address_line2, address_line3, address_line4 =
>  address.split( /\n\s*/ )
>
> puts address_line4


This method has a couple of minor shortcomings - it does not eliminate all 
unnecessary whitespace (specifically, it does not look at whitespace at 
the beginning of the address field - if there were any, nor does it look 
at trailing whitespace).

In that case, may I suggest the following solution?
(for readability, I have shortened Address_line1-4 to al1-4...


 	address = " 12, HouseName
 	            Street
 	            City
 	            Country "

 	# btw. you should never assume you'll just receive the 4 lines
 	# you were expecting - this is why I added in the *remains which
 	# will receive the extra lines, if any.
 	al1,al2,al3,al4,*remains =address.split("\n").map { |l| l.strip }

 	puts "A : '#{address}'"
 	puts "A1: '#{al1}'"
 	puts "A2: '#{al2}'"	# yes - for this example, I'm not checking
 	puts "A3: '#{al3}'"	# whether I get LESS than the 4 lines I
 	puts "A4: '#{al4}'"	# wanted...

 	if remains != []
 	  puts "oops... there are more than just the expected 4 lines"
 	  remains.each do |r|
 	    puts "  trailing line: #{r}"
 	  end
 	end


Running this will print:

 	A : ' 12, HouseName
 	            Street
 	            City
 	            Country '
 	A1: '12, HouseName'
 	A2: 'Street'
 	A3: 'City'
 	A4: 'Country'




Benedikt

   ALLIANCE, n.  In international politics, the union of two thieves who
     have their hands so deeply inserted in each other's pockets that
     they cannot separately plunder a third.
 			(Ambrose Bierce, The Devil's Dictionary)