DZone Snippets: strings code

Ruby Title Case

eliazar (eliazar parra) — Sat, 27 Oct 2007 00:41:10 GMT

Capitalize all words in a string with the briefest of snippets!



'some string here'.gsub(/\b\w/){$&.upcase}

String equality tester

Minimiscience (Guildorn Tanaleth) — Thu, 05 Jul 2007 03:22:26 GMT

If you want to test the equality of two strings and don't want the overhead of strcmp(), then this is the function for you.



_Bool strequals(char* a, char* b) {

 if (!a || !b) return 0;

 do {if (*a != *b) return 0; } while (*a++ && *b++);

 return 1;

}

create an array or split a long string seperated by tabs newlines carriage returns and commas.

mcarr (matt) — Sat, 09 Jun 2007 00:48:09 GMT

create an array or split a long string seperated by tabs newlines carriage returns and commas.

EG

emails = "skdjf@sdklfj.com sdflj@kj.com sldfj@klj.com, slkj@kjl.com,lskjdf@lkj.com, \r\nlkjkjl@kjk.com"

becomes

=> ["skdjf@sdklfj.com", "sdflj@kj.com", "sldfj@klj.com", "slkj@kjl.comlskjdf@lkj.com", "lkjkjl@kjk.com"]



emails = emails.split(/,/).join().split()

Actionscript _String Class

bgidge (Bryan Gidge) — Tue, 13 Feb 2007 19:19:55 GMT

dynamic class _String {

	// Replace a string or substrings within a string

	static function Replace (the_String, search_String, replace_String, occurrences, backward) {

		if (search_String == replace_String) return the_String;

		var found = 0;

		if (backward == true) {

			var pos = the_String.lastIndexOf(search_String);

			while (pos>= 0) {

				found++;

				var start_String = the_String.substr(0, pos);

				var end_String = the_String.substr(pos + search_String.length);

				the_String = start_String + replace_String + end_String;

				pos = the_String.lastIndexOf(search_String, start_String.length);

				if (found == occurrences) pos = -1;

			}

		}

		else {

			var pos = the_String.indexOf(search_String);

			while (pos>= 0) {

				found++;

				var start_String = the_String.substr(0, pos);

				var end_String = the_String.substr(pos + search_String.length);

				the_String = start_String + replace_String + end_String;

				pos = the_String.indexOf(search_String, pos + replace_String.length);

				if (found == occurrences) pos = -1;

			}

		}

		

		return the_String;

	}

	

	// Convert delimited (comma by default) String to an Array

	static function toArray(string, separator:String) {

		var list = new Array();

		if (typeof(string) == "string"){

			if (separator == undefined) separator = ",";

			if (string == null) return false;

			var currentStringPosition = 0;

			while (currentStringPosition				var nextIndex = string.indexOf(separator, currentStringPosition);

				if (nextIndex == -1) break;

				var word = string.slice(currentStringPosition, nextIndex);

				list.push(word);

				currentStringPosition = nextIndex+1;

			}

			if (list.length<1) list.push(string);

			else list.push(string.slice(currentStringPosition, string.length));

		} else {

			list.push(string);

		}

		return list;

	}

}

Convert String-Type the C++-Way

stayefeh (Sascha Tayefeh) — Wed, 17 Jan 2007 20:52:55 GMT

A very useful snipped that converts strings to/from various types.

Here's the header:



#include 

#include 

#include 

#include 

#include 

using namespace std;



#ifndef ST_STRING

#define ST_STRING





enum CONVTYPE { STRTOINT, STRTOFLOAT, INTTOSTR, STRTODOUBLE }; 



/*

 *  Convtype converts an integer to a string and a string 

 *  string to an integer, a float, or a double. The third argument

 *  of this method determines what to do:

 *  STRTOINT, STRTOFLOAT, INTTOSTR, and STRTODOUBLE.

 *

 */

void convtype(void*, void*, const int& );  

  

#endif

The appropiate implementation:



void convtype(void* inp, void* out, const int& convtype)

{

  istringstream isbuf;

  ostringstream osbuf;



  switch(convtype)

    {

    case STRTOINT:

      isbuf.str(*(string*) inp);

      isbuf >> *((int*) out);

      break;

    case STRTOFLOAT:

      isbuf.str(*(string*) inp);

      isbuf >> *((float*) out);

      break;

    case STRTODOUBLE:

      isbuf.str(*(string*) inp);

      isbuf >> *((double*) out);

      break;

    case INTTOSTR:

      osbuf << *((int*) inp);

      *((string*)out)=osbuf.str();

      break;

    }

  return;

}

Python String Breaking and Beginners Reg Ex All-in-One !

Williscool (William Harris) — Fri, 29 Sep 2006 19:09:51 GMT

http://mail.python.org/pipermail/python-list/2002-October/125367.html

// I found this on a python mailling list site

Ken wrote:
> "Padraig Brady" wrote in message
> news:3D9AFA69.2020804@Linux.ie...
>
>>Ken wrote:
>>
>>>Hi all, I am trying to do a simple word search engine. Is there an easy
>>
> way
>
>>>to break up a sentence into individual words so that I can use it to
>>
> compare
>
>>>without traversing through every character?
>>>
>>>Eg, something like this:
>>>from: "This is an example"
>>>to: ["This", "is", "an", "example"]
>>
>>You can use



"".split()

but that will not
>>deal with punctuation. For that you will
>>need re.
>>



import re

re.split('\W+', "This is an, example.")

>>
>>This however will create an empty list item
>>for the last '.'
>>
>>You can get around this by using the converse:



re.findall('\w+', "This is an, example.")

>>
>>Pádraig.
>
Does string.rstrip() get rid of the commas, fullstops etc.?

Don't get mixed up between strip and split.
The help for rstrip says "returns a string with trailing whitespace removed".
I.E. "123 " -> "123" however "123 ." doesn't change.

> Also, can you explain what the parameters "re.findall('\w+', "This is an,
> example.")" mean?

The \w+ is a regular expression that matches one or more
characters in the set [a-zA-Z0-9_]. I.E. it matches words.
Anything else (like spaces, punctuation) is not returned.



import re

mystring="This is an, example."

re.findall(r'\w+', mystring)     #all words

re.findall(r'\w*i\w*', mystring) #all words containing letter i

re.findall(r'\w{4,}', mystring)  #all words >= 4 letters

Pádraig.

Format strings like PRINT USING, for Ruby

Agent (Dustin Voss) — Sat, 26 Aug 2006 19:21:53 GMT

This is an extension to Ruby's String class. Just put this code in a file and include it. This basically takes a string and adds literals and padding to it. For example, you can format a phone number like this:



"5445556747".using('(###) ###-####', '', true)

   => (544) 555-6747



require 'strscan'



class String



  # Returns the string formatted according to a pattern.

  #

  # The pattern consists of placeholders and literals. The string is placed in

  # the placeholders, leaving the literals as they are. The result may be

  # truncated or padded if there are more placeholders than strings.

  #

  # Placeholders are '#' or '&'. Each '#' is replaced by one character from

  # the string, or the filler character if the string has no characters left.

  # The '&' is replaced by any remaining characters, or left out of the result

  # if there are no remaining characters. There can only be one '&' in the

  # pattern. If there is no '&', remaining characters are discarded.

  # 

  # '#' or '&' may be replaced by other characters if they are needed as

  # literals.

  #

  # Examples:

  # "123456789".using('###-##-####')

  #    => "123-45-6789"

  # "12345".using('###-##-####')

  #    => "123-45"

  # "12345".using('###-##-####', nil)

  #    => "12345"

  # "12345".using('###-##-####', ' ')

  #    => "123-45-    "

  # "5551212".using ('(###) ###-####', '', true)

  #    => "555-1212"

  # "873555121276668".using ('(###) ###-#### ext &', '', true)

  #    => "(873) 555-1212 ext 76668"

  # "KB5774X".using ('##-&-#')

  #    => "KB-5774-X"

  #

  # Parameters:

  # pattern -- The format string, see above.

  # fill    -- A string for padding. If the empty string, then the pattern is

  #            filled as much as possible, and the rest of the pattern is

  #            truncated. If nil, and the string does not fill the pattern,

  #            the string is returned unchanged.  Otherwise, the string is

  #            padded to fill the pattern, which is not truncated. Defaults to

  #            the empty string.

  # right   -- If true, the pattern is filled from right-to-left instead of

  #            from left-to-right, and truncated on the left instead of the

  #            right if needed. Default is false.

  # fixchar -- The single-character placeholder. Default is '#'.

  # remchar -- The remaining-character placeholder. Default is '&'.

  #

  def using(pattern, fill='', right=false, fixchar='#', remchar='&')



    remCount = pattern.count(remchar)

    raise ArgumentError.new("Too many #{remchar}") if remCount > 1

    raise ArgumentError.new("#{fixchar} too long") if fixchar.length > 1

    raise ArgumentError.new("#{remchar} too long") if remchar.length > 1

    raise ArgumentError.new("#{fill} too long")    if fill.length > 1

    remaining = remCount != 0

    slots = pattern.count(fixchar)



    # Return the string if it doesn't fit and we shouldn't even try,

    if fill.nil?

      return self if self.length < slots

      return self if self.length > slots and !remaining

    end



    # Pad and clone the string if necessary.

    source =  if fill.nil? || fill.empty? then

                self

              elsif right then

                self.rjust(slots, fill)

              else

                self.ljust(slots, fill)

              end

    

    # Truncate the string if necessary.

    if source.length > slots && !remaining then

      source = right ? source[-source.length, source.length] :

                       source[0, source.length]

    end



    # Truncate pattern if needed.

    if !fill.nil? && fill.empty? then

      

      if source.length < slots  # implies '&' can be ignored

        keepCount = source.length # Number of placeholders we are keeping

        leftmost, rightmost = 0, pattern.length - 1

        if right then

          # Look right-to-left until we find the last '#' to keep.

          # Loop starts at 1 because 0th placeholder is in the inject param.

          leftmost = (1...keepCount).inject(pattern.rindex(fixchar)) {

            |leftmost, n| pattern.rindex(fixchar, leftmost - 1) }

        else

          # Look left-to-right until we find the last '#' to keep.

          rightmost = (1...keepCount).inject(pattern.index(fixchar)) {

            |rightmost, n| pattern.index(fixchar, rightmost + 1) }

        end

        pattern = pattern[leftmost..rightmost]

        slots = pattern.count(fixchar)

      end

    

      # Trim empty '&' up to nearest placeholder. If a '&' goes empty, the

      # literals between it and the nearest '#' are probably also unnecessary.

      if source.length == slots then

        if pattern.match("^#{Regexp.escape(remchar)}") then

          pattern = pattern[pattern.index(fixchar) || 0 ... pattern.length]

        elsif pattern.match("#{Regexp.escape(remchar)}$") then

          pattern = pattern[0 ... (pattern.rindex(fixchar) + fixchar.length) || pattern.length]

        end

      end



    end

      

    # Figure out how long the remainder will be when we get to it.

    remSize = source.length - slots

    if remSize < 0 then remSize = 0; end

    

    # Make the result.

    scanner = ::StringScanner.new(pattern)

    sourceIndex = 0

    result = ''

    fixRegexp = Regexp.new(Regexp.escape(fixchar))

    remRegexp = Regexp.new(Regexp.escape(remchar))

    while not scanner.eos?

      if scanner.scan(fixRegexp) then

        result += source[sourceIndex].chr

        sourceIndex += 1

      elsif scanner.scan(remRegexp) then

        result += source[sourceIndex, remSize]

        sourceIndex += remSize

      else

        result += scanner.getch

      end

    end

    

    result

  end

end

Text to HTML converter (PHP 4+)

fzero (Fabio FZero) — Tue, 20 Jun 2006 23:01:21 GMT

Simple function to convert a text into formatted HTML in PHP. The function implements some text cleanups (double space removal) and accepts some HTML in the text, like links (a href), lists (ul, ol), blockquotes and tables. This makes it perfect for use inside custom-made blogging engines and CMSs. There's also an implementation of case-insensitive search/replace for php < 5.





function stri_replace( $find, $replace, $string ) {

// Case-insensitive str_replace()



  $parts = explode( strtolower($find), strtolower($string) );



  $pos = 0;



  foreach( $parts as $key=>$part ){

    $parts[ $key ] = substr($string, $pos, strlen($part));

    $pos += strlen($part) + strlen($find);

  }



  return( join( $replace, $parts ) );

}





function txt2html($txt) {

// Transforms txt in html



  //Kills double spaces and spaces inside tags.

  while( !( strpos($txt,'  ') === FALSE ) ) $txt = str_replace('  ',' ',$txt);

  $txt = str_replace(' >','>',$txt);

  $txt = str_replace('< ','<',$txt);



  //Transforms accents in html entities.

  $txt = htmlentities($txt);



  //We need some HTML entities back!

  $txt = str_replace('"','"',$txt);

  $txt = str_replace('<','<',$txt);

  $txt = str_replace('>','>',$txt);

  $txt = str_replace('&','&',$txt);



  //Ajdusts links - anything starting with HTTP opens in a new window

  $txt = stri_replace("  $txt = stri_replace("

  //Basic formatting

  $eol = ( strpos($txt,"\r") === FALSE ) ? "\n" : "\r\n";

  $html = ''.str_replace("$eol$eol","
",$txt).'';

  $html = str_replace("$eol","
\n",$html);

  $html = str_replace("
","\n\n",$html);

  $html = str_replace("
"," ",$html);



  //Wipes 
 after block tags (for when the user includes some html in the text).

  $wipebr = Array("table","tr","td","blockquote","ul","ol","li");



  for($x = 0; $x < count($wipebr); $x++) {



    $tag = $wipebr[$x];

    $html = stri_replace("<$tag>
","<$tag>",$html);

    $html = stri_replace("
","",$html);



  }



  return $html;

}



?>

Capitalizing titles in Ruby - another take...

s0nspark (Tim Ferrell) — Sat, 06 Aug 2005 00:09:31 GMT

This code was inspired by Peter's code from May 17...

I basically extended his idea to be more flexible and added ! methods to modify the string in place. I chose to use a different regex selector because using "\b" breaks on apostrophes and leave you with words like "You'Re" instead of "You're"...





class String



  def titlecase()

    ignore_list = %w{of etc and by the for on is at to but nor or a via}

    capitalize_all_ex(ignore_list)

  end



  def titlecase!()

    ignore_list = %w{of etc and by the for on is at to but nor or a via}

    capitalize_all_ex!(ignore_list)

  end



  def capitalize_all(force_downcase = true)

    ignore_list = %w{}

    capitalize_all_ex(ignore_list, force_downcase)

  end



  def capitalize_all!(force_downcase = true)

    ignore_list = %w{}

    capitalize_all_ex!(ignore_list, force_downcase)

  end



  def capitalize_all_ex(ignore_list, force_downcase = true)

    # if force_downcase is true then the 

    # string is, um, downcased first :-)

    if force_downcase

      self.downcase.gsub(/[\w\']+/){ |w| 

        ignore_list.include?(w) ? w : w.capitalize  

      }

    else

      self.gsub(/[\w\']+/){ |w| 

        ignore_list.include?(w) ? w : w.capitalize  

      }

    end

  end



  def capitalize_all_ex!(ignore_list, force_downcase = true)

    if force_downcase

      self.replace(self.downcase.gsub(/[\w\']+/){ |w| 

        ignore_list.include?(w) ? w : w.capitalize  

      })

    else

      self.replace(self.gsub(/[\w\']+/){ |w| 

        ignore_list.include?(w) ? w : w.capitalize  

      })

    end

  end

end

Truncate String by Words

banderson623 (Brian Anderson) — Sun, 26 Jun 2005 02:18:59 GMT

This will take a phrase and truncate it at the word level





function trunc($phrase, $max_words)

{

   $phrase_array = explode(' ',$phrase);

   if(count($phrase_array) > $max_words && $max_words > 0)

      $phrase = implode(' ',array_slice($phrase_array, 0, $max_words)).'...'  

   return $phrase;

}

?>