--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/orange/core/string.d	Tue Oct 19 10:22:10 2010 +0200
@@ -0,0 +1,888 @@
+/**
+ * Copyright: Copyright (c) 2008-2009 Jacob Carlborg. All rights reserved.
+ * Authors: Jacob Carlborg
+ * Version: Initial created: 2008
+ * License: $(LINK2 http://www.boost.org/LICENSE_1_0.txt, Boost Software License 1.0)
+ * 
+ */
+module orange.core.string;
+
+public import orange.util.collection.Array;
+
+version (Tango)
+{
+	static import tango.stdc.stringz;
+	import tango.text.Unicode : toFold, isDigit;
+	import tango.text.convert.Utf;
+	import tango.text.Util;
+	
+	alias tango.stdc.stringz.toStringz toStringz;
+	alias tango.stdc.stringz.toString16z toString16z;
+	alias tango.stdc.stringz.toString32z toString32z;
+	
+	alias tango.stdc.stringz.fromStringz fromStringz;
+	alias tango.stdc.stringz.fromString16z fromString16z;
+	alias tango.stdc.stringz.fromString32z fromString32z;
+	
+	alias tango.text.convert.Utf.toString16 toString16;
+	alias tango.text.convert.Utf.toString32 toString32;
+}
+
+else
+{	
+	import std.string;
+	import std.utf;
+	import std.ctype : isxdigit;
+	
+	version = Phobos;
+	
+	private alias std.string.tolower toFold;
+	
+	alias std.utf.toUTF8 toString;
+	alias std.utf.toUTF16 toString16;
+	alias std.utf.toUTF32 toString32;
+	
+	alias std.string.toStringz toStringz;
+	alias std.utf.toUTF16z toString16z;
+	
+	alias std.string.toString fromStringz;
+}
+
+version (Tango)
+{
+	/**
+	 * string alias
+	 */
+	alias char[] string;
+
+	/**
+	 * wstring alias
+	 */
+	alias wchar[] wstring;
+
+	/**
+	 * dstring alias
+	 */
+	alias dchar[] dstring;
+}
+
+/**
+ * Compares the $(D_PSYMBOL string) to another $(D_PSYMBOL string), ignoring case
+ * considerations.  Two strings are considered equal ignoring case if they are of the
+ * same length and corresponding characters in the two strings  are equal ignoring case.
+ * 
+ * Params:
+ *     str = The $(D_PSYMBOL string) first string to compare to
+ *     anotherString = The $(D_PSYMBOL string) to compare the first $(D_PSYMBOL string) with
+ *     
+ * Returns: $(D_KEYWORD true) if the arguments is not $(D_KEYWORD null) and it
+ *          represents an equivalent $(D_PSYMBOL string) ignoring case; $(D_KEYWORD false) otherwise
+ *          
+ * Throws: AssertException if the length of any of the strings is 0
+ *          
+ * See_Also: opEquals(Object)
+ */
+bool equalsIgnoreCase (string str, string anotherString)
+in
+{
+	assert(str.length > 0, "mambo.string.equalsIgnoreCase: The length of the first string was 0");
+	assert(anotherString.length > 0, "mambo.string.equalsIgnoreCase: The length of the second string was 0");
+}
+body
+{	
+	if (str == anotherString)
+		return true;
+
+	return toFold(str) == toFold(anotherString);
+}
+
+/**
+ * Compares the $(D_PSYMBOL wstring) to another $(D_PSYMBOL wstring), ignoring case
+ * considerations. Two wstrings are considered equal ignoring case if they are of the
+ * same length and corresponding characters in the two wstrings are equal ignoring case.
+ * 
+ * Params:
+ *     str = The $(D_PSYMBOL wstring) first string to compre to
+ *     anotherString = The $(D_PSYMBOL wstring) to compare the first $(D_PSYMBOL wstring) against
+ *     
+ * Returns: $(D_KEYWORD true) if the argument is not $(D_KEYWORD null) and it
+ *          represents an equivalent $(D_PSYMBOL wstring) ignoring case; (D_KEYWORD
+ *          false) otherwise
+ *          
+ * Throws: AssertException if the length of any of the wstrings is 0
+ *          
+ * See_Also: opEquals(Object)
+ */
+bool equalsIgnoreCase (wstring str, wstring anotherString)
+in
+{
+	assert(str.length > 0, "mambo.string.equalsIgnoreCase: The length of the first string was 0");
+	assert(anotherString.length > 0, "mambo.string.equalsIgnoreCase: The length of the second string was 0");
+}
+body
+{
+	if (str == anotherString)
+		return true;
+
+	version (Tango)
+		return toFold(str) == toFold(anotherString);
+
+	else
+		return toFold(toUTF8(str)) == toFold(toUTF8(anotherString));
+}
+
+/**
+ * Compares the $(D_PSYMBOL dstring) to another $(D_PSYMBOL dstring), ignoring case
+ * considerations. Two wstrings are considered equal ignoring case if they are of the
+ * same length and corresponding characters in the two wstrings are equal ignoring case.
+ * 
+ * Params:
+ *     str = The $(D_PSYMBOL dstring) first string to compare to
+ *     anotherString = The $(D_PSYMBOL wstring) to compare the first $(D_PSYMBOL dstring) against
+ *     
+ * Returns: $(D_KEYWORD true) if the argument is not $(D_KEYWORD null) and it
+ *          represents an equivalent $(D_PSYMBOL dstring) ignoring case; $(D_KEYWORD false) otherwise
+ *          
+ * Throws: AssertException if the length of any of the dstrings are 0
+ *          
+ * See_Also: opEquals(Object)
+ */
+bool equalsIgnoreCase (dstring str, dstring anotherString)
+in
+{
+	assert(str.length > 0, "mambo.string.equalsIgnoreCase: The length of the first string was 0");
+	assert(anotherString.length > 0, "mambo.string.equalsIgnoreCase: The length of the second string was 0");
+}
+body
+{
+	if (str == anotherString)
+		return true;
+
+	version (Tango)
+		return toFold(str) == toFold(anotherString);
+
+	else
+		return toFold(toUTF8(str)) == toFold(toUTF8(anotherString));
+}
+
+/**
+ * Returns the char value at the specified index. An index ranges from 0 to length - 1.
+ * The first $(D_KEYWORD char) value of the sequence is at index 0, the next at index 1,
+ * and so on, as for array indexing.
+ * 
+ * Params:
+ * 	   str = the string to get the $(D_KEYWORD char) from
+ *     index = the index of the $(D_KEYWORD char) value.
+ *     
+ * Returns: the $(D_KEYWORD char) value at the specified index of the string.
+ *          The first $(D_KEYWORD char) value is at index 0.
+ * 
+ * Throws: AssertException if the length of the string is 0
+ * Throws: AssertException if the $(D_CODE index) argument is
+ *         not less than the length of the string.
+ */
+char charAt (string str, size_t index)
+in
+{
+	assert(str.length > 0, "mambo.string.charAt: The length of the string was 0");
+	assert(index <= str.length, "mambo.string.charAt: The index was to greater than the length of the string");
+}
+body
+{
+	return str[index];
+}
+
+/**
+ * Returns the $(D_KEYWORD char) value at the specified index. An index ranges from 0 to
+ * length - 1. The first $(D_KEYWORD char) value of the sequence is at index 0, the next
+ * at index 1, and so on, as for array indexing.
+ * 
+ * Params:
+ * 	   str = the wstring to get the $(D_KEYWORD char) from
+ *     index = the index of the $(D_KEYWORD char) value.
+ *     
+ * Returns: the $(D_KEYWORD char) value at the specified index of the wstring.
+ *          The first $(D_KEYWORD char) value is at index 0.
+ * 
+ * Throws: AssertException if the length of the wstring is 0
+ * Throws: AssertException if the $(D_CODE index) argument is
+ *         not less than the length of the wstring.
+ */
+wchar charAt (wstring str, size_t index)
+in
+{
+	assert(str.length > 0, "mambo.string.charAt: The length of the string was 0");
+	assert(index <= str.length, "mambo.string.charAt: The index was to greater than the length of the string");
+}
+body
+{
+	return str[index];
+}
+
+/**
+ * Returns the $(D_KEYWORD char) value at the specified index. An index ranges from 0 to
+ * length - 1. The first $(D_KEYWORD char) value of the sequence is at index 0, the next
+ * at index 1, and so on, as for array indexing.
+ * 
+ * Params:
+ * 	   str = the dstring to get the $(D_KEYWORD char) from
+ *     index = the index of the $(D_KEYWORD char) value.
+ *     
+ * Returns: the $(D_KEYWORD char) value at the specified index of the dstring.
+ *          The first $(D_KEYWORD char) value is at index 0.
+ * 
+ * Throws: AssertException if the length of the dstring is 0
+ * Throws: AssertException if the $(D_CODE index) argument is
+ *         not less than the length of the dstring.
+ */
+dchar charAt (dstring str, size_t index)
+in
+{
+	assert(str.length > 0, "mambo.string.charAt: The length of the string was 0");
+	assert(index <= str.length, "mambo.string.charAt: The index was to greater than the length of the string");
+}
+body
+{
+	return str[index];
+}
+
+/**
+ * Returns a new string that is a substring of the specified string. The substring begins
+ * at the specified $(D_PARAM beginIndex) and extends to the character at index
+ * $(D_PARAM endIndex) - 1. Thus the length of the substring is $(D_PARAM endIndex - beginIndex).
+ * 
+ * Examples:
+ * ---
+ * "hamburger".substring(4, 8) returns "urge"
+ * "smiles".substring(1, 5) returns "mile"
+ * ---
+ * 
+ * Params:
+ * 	   str = the string to get the substring from
+ *     beginIndex = the beginning index, inclusive.
+ *     endIndex = the ending index, exclusive.
+ *     
+ * Returns: the specified substring.
+ * 
+ * Throws: AssertException if the length of the string is 0
+ * Throws: AssertException if the $(D_PARAM beginIndex) is 
+ * 		   larger than $(D_PARAM endIndex).
+ * Throws: AssertException if $(D_PARAM endIndex) is larger than the 
+ *  	   length of the $(D_PSYMBOL string).
+ */
+string substring (string str, size_t beginIndex, size_t endIndex)
+in
+{
+	assert(str.length > 0, "mambo.string.substring: The length of the string was 0");
+	assert(beginIndex < endIndex, "mambo.string.substring: The first index was greater the second");
+	assert(endIndex <= str.length, "mambo.string.substring: The second index was greater then the length of the string");
+}
+body
+{
+	version (Tango) return str[beginIndex .. endIndex].dup;
+	else return str[beginIndex .. endIndex].idup;
+}
+
+/**
+ * Returns a new string that is a substring of the specified string. The substring begins
+ * at the specified $(D_PARAM beginIndex) and extends to the character at index
+ * $(D_PARAM endIndex) - 1. Thus the length of the substring is $(D_PARAM endIndex - beginIndex).
+ * 
+ * Examples:
+ * ---
+ * "hamburger".substring(4, 8) returns "urge"
+ * "smiles".substring(1, 5) returns "mile"
+ * ---
+ * 
+ * Params:
+ * 	   str = the string to get the substring from
+ *     beginIndex = the beginning index, inclusive.
+ *     endIndex = the ending index, exclusive.
+ *     
+ * Returns: the specified substring.
+ * 
+ * Throws: AssertException if the length of the string is 0
+ * Throws: AssertException if the $(D_PARAM beginIndex) is 
+ * 		   larger than $(D_PARAM endIndex).
+ * Throws: AssertException if $(D_PARAM endIndex) is larger than the 
+ *  	   length of the $(D_PSYMBOL string).
+ */
+wstring substring (wstring str, size_t beginIndex, size_t endIndex)
+in
+{
+	assert(str.length > 0, "mambo.string.substring: The length of the string was 0");
+	assert(beginIndex < endIndex, "mambo.string.substring: The first index was greater the second");
+	assert(endIndex <= str.length, "mambo.string.substring: The second index was greater then the length of the string");
+}
+body
+{
+	version (Tango) return str[beginIndex .. endIndex].dup;
+	else return str[beginIndex .. endIndex].idup;
+}
+
+/**
+ * Returns a new string that is a substring of the specified string. The substring begins
+ * at the specified $(D_PARAM beginIndex) and extends to the character at index
+ * $(D_PARAM endIndex) - 1. Thus the length of the substring is $(D_PARAM endIndex - beginIndex).
+ * 
+ * Examples:
+ * ---
+ * "hamburger".substring(4, 8) returns "urge"
+ * "smiles".substring(1, 5) returns "mile"
+ * ---
+ * 
+ * Params:
+ * 	   str = the string to get the substring from
+ *     beginIndex = the beginning index, inclusive.
+ *     endIndex = the ending index, exclusive.
+ *     
+ * Returns: the specified substring.
+ * 
+ * Throws: AssertException if the length of the string is 0
+ * Throws: AssertException if the $(D_PARAM beginIndex) is 
+ * 		   larger than $(D_PARAM endIndex).
+ * Throws: AssertException if $(D_PARAM endIndex) is larger than the 
+ *  	   length of the $(D_PSYMBOL string).
+ */
+dstring substring (dstring str, size_t beginIndex, size_t endIndex)
+in
+{
+	assert(str.length > 0, "mambo.string.substring: The length of the string was 0");
+	assert(beginIndex < endIndex, "mambo.string.substring: The first index was greater the second");
+	assert(endIndex <= str.length, "mambo.string.substring: The second index was greater then the length of the string");
+}
+body
+{
+	version (Tango) return str[beginIndex .. endIndex].dup;
+	else return str[beginIndex .. endIndex].idup;
+}
+
+/**
+ * Returns a new string that is a substring of the specified string. The substring begins
+ * with the character at the specified index and extends to the end of the string. 
+ * 
+ * Examples:
+ * ---
+ * "unhappy".substring(2) returns "happy"
+ * "Harbison".substring(3) returns "bison"
+ * "emptiness".substring(9) returns "" (an empty string)
+ * ---
+ * 
+ * Params:
+ *     str = the string to get the substring from
+ *     beginIndex = the beginning index, inclusive
+ *     
+ * Returns: the specified substring
+ * 
+ * Throws: AssertException if the length of the string is 0
+ * Throws: AssertException if the $(D_PARAM beginIndex) is 
+ * 		   larger than the length of the string.
+ */
+string substring (string str, size_t index)
+in
+{
+	assert(str.length > 0, "mambo.string.substring: The length of the string was 0");
+	assert(index < str.length, "mambo.string.substring: The index was greater than the length of the string");
+}
+body
+{
+	return str.substring(index, str.length);
+}
+
+/**
+ * Returns a new string that is a substring of the specified string. The substring begins
+ * with the character at the specified index and extends to the end of the string. 
+ * 
+ * Examples:
+ * ---
+ * "unhappy".substring(2) returns "happy"
+ * "Harbison".substring(3) returns "bison"
+ * "emptiness".substring(9) returns "" (an empty string)
+ * ---
+ * 
+ * Params:
+ *     str = the string to get the substring from
+ *     beginIndex = the beginning index, inclusive
+ *     
+ * Returns: the specified substring
+ * 
+ * Throws: AssertException if the length of the string is 0
+ * Throws: AssertException if the $(D_PARAM beginIndex) is 
+ * 		   larger than the length of the string.
+ */
+wstring substring (wstring str, size_t index)
+in
+{
+	assert(str.length > 0, "mambo.string.substring: The length of the string was 0");
+	assert(index < str.length, "mambo.string.substring: The index was greater than the length of the string");
+}
+body
+{
+	return str.substring(index, str.length);
+}
+
+/**
+ * Returns a new string that is a substring of the specified string. The substring begins
+ * with the character at the specified index and extends to the end of the string. 
+ * 
+ * Examples:
+ * ---
+ * "unhappy".substring(2) returns "happy"
+ * "Harbison".substring(3) returns "bison"
+ * "emptiness".substring(9) returns "" (an empty string)
+ * ---
+ * 
+ * Params:
+ *     str = the string to get the substring from
+ *     beginIndex = the beginning index, inclusive
+ *     
+ * Returns: the specified substring
+ * 
+ * Throws: AssertException if the length of the string is 0
+ * Throws: AssertException if the $(D_PARAM beginIndex) is 
+ * 		   larger than the length of the string.
+ */
+dstring substring (dstring str, size_t index)
+in
+{
+	assert(str.length > 0, "mambo.string.substring: The length of the string was 0");
+	assert(index < str.length, "mambo.string.substring: The index was greater than the length of the string");
+}
+body
+{
+	return str.substring(index, str.length);
+}
+
+/**
+ * Returns a new string that is a substring of the given string.
+ * 
+ * This substring is the character sequence that starts at character
+ * position pos and has a length of n characters.
+ * 
+ * Params:
+ *     str = the string to get the substring from
+ *     pos = position of a character in the current string to be used 
+ *     		 as starting character for the substring.
+ *     n = Length of the substring. If this value would make the 
+ *     	   substring to span past the end of the current string content,
+ *     	   only those characters until the end of the string are used. 
+ *     	   size_t.max is the greatest possible value for an element of
+ *     	   type size_t, therefore, when this value is used, all the
+ *     	   characters between pos and the end of the string are used as
+ *     	   the initialization substring.
+ *     
+ * Returns: a string containing a substring of the given string
+ * 
+ * Throws: AssertException if pos is greater than the length of the string
+ */
+string substr (string str, size_t pos = 0, size_t n = size_t.max)
+in
+{
+	assert(pos < str.length, "mambo.string.substr: The given position was greater than the length of the string.");
+}
+body
+{
+	size_t end;
+	
+	if (n == size_t.max)
+		end = str.length;
+	
+	else
+	{
+		end = pos + n;
+		
+		if (end > str.length)
+			end = str.length;
+	}
+	
+	version (Tango) return str[pos .. end].dup;
+	else return str[pos .. end].idup;
+}
+
+/**
+ * Returns a new string that is a substring of the given string.
+ * 
+ * This substring is the character sequence that starts at character
+ * position pos and has a length of n characters.
+ * 
+ * Params:
+ *     str = the string to get the substring from
+ *     pos = position of a character in the current string to be used 
+ *     		 as starting character for the substring.
+ *     n = Length of the substring. If this value would make the 
+ *     	   substring to span past the end of the current string content,
+ *     	   only those characters until the end of the string are used. 
+ *     	   size_t.max is the greatest possible value for an element of
+ *     	   type size_t, therefore, when this value is used, all the
+ *     	   characters between pos and the end of the string are used as
+ *     	   the initialization substring.
+ *     
+ * Returns: a string containing a substring of the given string
+ * 
+ * Throws: AssertException if pos is greater than the length of the string
+ */
+wstring substr (wstring str, size_t pos = 0, size_t n = size_t.max)
+in
+{
+	assert(pos < str.length, "mambo.string.substr: The given position was greater than the length of the string.");
+}
+body
+{
+	size_t end;
+	
+	if (n == size_t.max)
+		end = str.length;
+	
+	else
+	{
+		end = pos + n;
+		
+		if (end > str.length)
+			end = str.length;
+	}
+	
+	version (Tango) return str[pos .. end].dup;
+	else return str[pos .. end].idup;
+}
+
+/**
+ * Returns a new string that is a substring of the given string.
+ * 
+ * This substring is the character sequence that starts at character
+ * position pos and has a length of n characters.
+ * 
+ * Params:
+ *     str = the string to get the substring from
+ *     pos = position of a character in the current string to be used 
+ *     		 as starting character for the substring.
+ *     n = Length of the substring. If this value would make the 
+ *     	   substring to span past the end of the current string content,
+ *     	   only those characters until the end of the string are used. 
+ *     	   size_t.max is the greatest possible value for an element of
+ *     	   type size_t, therefore, when this value is used, all the
+ *     	   characters between pos and the end of the string are used as
+ *     	   the initialization substring.
+ *     
+ * Returns: a string containing a substring of the given string
+ * 
+ * Throws: AssertException if pos is greater than the length of the string
+ */
+dstring substr (dstring str, size_t pos = 0, size_t n = size_t.max)
+in
+{
+	assert(pos < str.length, "mambo.string.substr: The given position was greater than the length of the string.");
+}
+body
+{
+	size_t end;
+	
+	if (n == size_t.max)
+		end = str.length;
+	
+	else
+	{
+		end = pos + n;
+		
+		if (end > str.length)
+			end = str.length;
+	}
+	
+	version (Tango) return str[pos .. end].dup;
+	else return str[pos .. end].idup;
+}
+
+/**
+ * Finds the first occurence of sub in str
+ * 
+ * Params:
+ *     str = the string to find in
+ *     sub = the substring to find
+ *     start = where to start finding
+ *     
+ * Returns: the index of the substring or size_t.max when nothing was found
+ */
+size_t find (string str, string sub)
+{
+	version (Tango)
+	{
+		size_t index = str.locatePattern(sub);
+		
+		if (index == str.length)
+			return size_t.max;
+		
+		return index;
+	}
+	
+	else
+		return std.string.indexOf(str, sub);
+	
+}
+
+/**
+ * Finds the first occurence of sub in str
+ * 
+ * Params:
+ *     str = the string to find in
+ *     sub = the substring to find
+ *     start = where to start finding
+ *     
+ * Returns: the index of the substring or size_t.max when nothing was found
+ */
+size_t find (wstring str, wstring sub)
+{
+	version (Tango)
+	{
+		size_t index = str.locatePattern(sub);
+		
+		if (index == str.length)
+			return size_t.max;
+		
+		return index;
+	}
+	
+	else
+		return std.string.indexOf(str, sub);
+}
+
+/**
+ * Finds the first occurence of sub in str
+ * 
+ * Params:
+ *     str = the string to find in
+ *     sub = the substring to find
+ *     start = where to start finding
+ *     
+ * Returns: the index of the substring or size_t.max when nothing was found
+ */
+size_t find (dstring str, dstring sub)
+{
+	version (Tango)
+	{
+		size_t index = str.locatePattern(sub);
+		
+		if (index == str.length)
+			return size_t.max;
+		
+		return index;
+	}
+	
+	else
+		return std.string.indexOf(str, sub);
+}
+
+/**
+ * Compares to strings, ignoring case differences. Returns 0 if the content
+ * matches, less than zero if a is "less" than b, or greater than zero
+ * where a is "bigger".
+ * 
+ * Params:
+ *     a = the first array 
+ *     b = the second array
+ *     end = the index where the comparision will end
+ *     
+ * Returns: Returns 0 if the content matches, less than zero if a is 
+ * 			"less" than b, or greater than zero where a is "bigger".
+ * 
+ * See_Also: mambo.collection.array.compare
+ */
+int compareIgnoreCase (U = size_t) (string a, string b, U end = U.max)
+{
+	return a.toFold().compare(b.toFold(), end);
+}
+
+/**
+ * Compares to strings, ignoring case differences. Returns 0 if the content
+ * matches, less than zero if a is "less" than b, or greater than zero
+ * where a is "bigger".
+ * 
+ * Params:
+ *     a = the first array 
+ *     b = the second array
+ *     end = the index where the comparision will end
+ *     
+ * Returns: Returns 0 if the content matches, less than zero if a is 
+ * 			"less" than b, or greater than zero where a is "bigger".
+ * 
+ * See_Also: mambo.collection.array.compare
+ */
+int compareIgnoreCase (U = size_t) (wstring a, wstring b, U end = U.max)
+{
+	return a.toFold().compare(b.toFold(), end);
+}
+
+/**
+ * Compares to strings, ignoring case differences. Returns 0 if the content
+ * matches, less than zero if a is "less" than b, or greater than zero
+ * where a is "bigger".
+ * 
+ * Params:
+ *     a = the first array 
+ *     b = the second array
+ *     end = the index where the comparision will end
+ *     
+ * Returns: Returns 0 if the content matches, less than zero if a is 
+ * 			"less" than b, or greater than zero where a is "bigger".
+ * 
+ * See_Also: mambo.collection.array.compare
+ */
+int compareIgnoreCase (U = size_t) (dstring a, dstring b, U end = U.max)
+{
+	return a.toFold().compare(b.toFold(), end);
+}
+
+/**
+ * Compares to strings, ignoring case differences. Returns 0 if the content
+ * matches, less than zero if a is "less" than b, or greater than zero
+ * where a is "bigger".
+ * 
+ * Params:
+ *     a = the first array 
+ *     b = the second array
+ *     end = the index where the comparision will end
+ *     
+ * Returns: Returns 0 if the content matches, less than zero if a is 
+ * 			"less" than b, or greater than zero where a is "bigger".
+ * 
+ * See_Also: mambo.string.compareIgnoreCase
+ */
+alias compareIgnoreCase icompare;
+
+/**
+ * Checks if the given character is a hexdecimal digit character.
+ * Hexadecimal digits are any of: 0 1 2 3 4 5 6 7 8 9 a b c d e f A B C D E F
+ * 
+ * Params:
+ *     ch = the character to be checked
+ *     
+ * Returns: true if the given character is a hexdecimal digit character otherwise false
+ */
+bool isHexDigit (dchar ch)
+{
+	version (Tango)
+	{
+		switch (ch)
+		{
+			case 'A': return true;				
+			case 'B': return true;
+			case 'C': return true;
+			case 'D': return true;
+			case 'E': return true;
+			case 'F': return true;
+			
+			case 'a': return true;
+			case 'b': return true;
+			case 'c': return true;
+			case 'd': return true;
+			case 'e': return true;
+			case 'f': return true;
+			
+			default: break;
+		}
+		
+		if (isDigit(ch))
+			return true;
+	}
+
+	else
+		if (isxdigit(ch) != 0)
+			return true;
+		
+	return false;
+}
+
+/*version (Tango)
+{
+	string toString (string str)
+	{
+		return str;
+	}
+	
+	string toString (wstring str)
+	{
+		return tango.text.convert.Utf.toString(str);
+	}
+	
+	string toString (dstring str)
+	{
+		return tango.text.convert.Utf.toString(str);
+	}
+}*/
+
+version (Phobos)
+{	
+	/**
+	 * Converts the given string to C-style 0 terminated string.
+	 * 
+	 * Params:
+	 *     str = the string to convert
+	 *     
+	 * Returns: the a C-style 0 terminated string.
+	 */
+	dchar* toString32z (dstring str)
+	{
+		return (str ~ '\0').dup.ptr;
+	}
+	
+	/**
+	 * Converts a C-style 0 terminated string to a wstring
+	 * 
+	 * Params:
+	 *     str = the C-style 0 terminated string
+	 *     
+	 * Returns: the converted wstring
+	 */
+	wstring fromString16z (wchar* str)
+	{
+		return str[0 .. strlen(str)].idup;
+	}
+	
+	/**
+	 * Converts a C-style 0 terminated string to a dstring
+	 * Params:
+	 *     str = the C-style 0 terminated string
+	 *     
+	 * Returns: the converted dstring
+	 */
+	dstring fromString32z (dchar* str)
+	{
+		return str[0 .. strlen(str)].idup;
+	}
+	
+	/**
+	 * Gets the length of the given C-style 0 terminated string
+	 * 
+	 * Params:
+	 *     str = the C-style 0 terminated string to get the length of
+	 *     
+	 * Returns: the length of the string
+	 */
+	size_t strlen (wchar* str)
+	{
+		size_t i = 0;
+		
+		if (str)
+			while(*str++)
+				++i;
+		
+		return i;
+	}
+	
+	/**
+	 * Gets the length of the given C-style 0 terminated string
+	 * 
+	 * Params:
+	 *     str = the C-style 0 terminated string to get the length of
+	 *     
+	 * Returns: the length of the string
+	 */
+	size_t strlen (dchar* str)
+	{
+		size_t i = 0;
+		
+		if (str)
+			while(*str++)
+				++i;
+		
+		return i;
+	}
+}
\ No newline at end of file