strings/lib/src/strings.dart - third_party/dart-pkg - Git at Google

 part of strings;

 const int _ASCII_END = 0x7f;

 const int _ASCII_START = 0x0;

 const int _C0_END = 0x1f;

 const int _C0_START = 0x00;

 const int _UNICODE_END = 0x10ffff;

 const int _DIGIT = 0x1;

 const int _LOWER = 0x2;

 const int _UNDERSCORE = 0x4;

 const int _UPPER = 0x8;

 const int _ALPHA = _LOWER | _UPPER;

 const int _ALPHA_NUM = _ALPHA | _DIGIT;

 const int _VALID = _ALPHA_NUM | _UNDERSCORE;

 final List<int> _ascii = <int>[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8,
     8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 4, 0, 2, 2, 2, 2,
     2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 0, 0,
     0];

 /**
  * Returns a string in the form "UpperCamelCase" or "lowerCamelCase".
  *
  * Example:
  *      print(camelize("dart_vm"));
  *      => DartVm
  */
 String camelize(String string, [bool lower = false]) {
   if (string == null) {
     throw new ArgumentError("string: $string");
   }

   if (string.length == 0) {
     return string;
   }

   string = string.toLowerCase();
   var capitlize = true;
   var length = string.length;
   var position = 0;
   var remove = false;
   var sb = new StringBuffer();
   for (var i = 0; i < length; i++) {
     var s = string[i];
     var c = s.codeUnitAt(0);
     var flag = 0;
     if (c <= _ASCII_END) {
       flag = _ascii[c];
     }

     if (capitlize && flag & _ALPHA != 0) {
       if (lower && position == 0) {
         sb.write(s);
       } else {
         sb.write(s.toUpperCase());
       }

       capitlize = false;
       remove = true;
       position++;
     } else {
       if (flag & _UNDERSCORE != 0) {
         if (!remove) {
           sb.write(s);
           remove = true;
         }

         capitlize = true;
       } else {
         if (flag & _ALPHA_NUM != 0) {
           capitlize = false;
           remove = true;
         } else {
           capitlize = true;
           remove = false;
           position = 0;
         }

         sb.write(s);
       }
     }
   }

   return sb.toString();
 }

 /**
  * Returns a string with capitalized first character.
  *
  * Example:
  *     print(capitalize("dart"));
  *     => Dart
  */
 String capitalize(String string) {
   if (string == null) {
     throw new ArgumentError("string: $string");
   }

   if (string.length == 0) {
     return string;
   }

   return string[0].toUpperCase() + string.substring(1);
 }

 /**
  * Returns an escaped string.
  *
  * Example:
  *     print(escape("Hello 'world' \n"));
  *     => Hello \'world\' \n
  */
 String escape(String string, [String encode(int charCode)]) {
   if (string == null) {
     throw new ArgumentError("string: $string");
   }

   if (string.length == 0) {
     return string;
   }

   if (encode == null) {
     encode = toUnicode;
   }

   var sb = new StringBuffer();
   var i = 0;
   for (var c in string.runes) {
     if (c >= _C0_START && c <= _C0_END) {
       switch (c) {
         case 9:
           sb.write("\\t");
           break;
         case 10:
           sb.write("\\n");
           break;
         case 13:
           sb.write("\\r");
           break;
         default:
           sb.write(encode(c));
       }

     } else if (c >= _ASCII_START && c <= _ASCII_END) {
       switch (c) {
         case 34:
           sb.write("\\\"");
           break;
         case 36:
           sb.write("\\\$");
           break;
         case 39:
           sb.write("\\\'");
           break;
         case 92:
           sb.write("\\\\");
           break;
         default:
           sb.write(string[i]);
       }

     } else if (_isPrintable(c)) {
      sb.write(string[i]);
     } else {
       sb.write(encode(c));
     }

     i++;
   }

   return sb.toString();
 }

 /**
  * Returns true if the string does not contain upper case letters; otherwise
  * false;
  *
  * Example:
  *     print(isLowerCase("camelCase"));
  *     => false
  *
  *     print(isLowerCase("dart"));
  *     => true
  *
  *     print(isLowerCase(""));
  *     => false
  */
 bool isLowerCase(String string) {
   if (string == null) {
     throw new ArgumentError("string: $string");
   }

   if (string.length == 0) {
     return true;
   }

   var length = string.length;
   for (var i = 0; i < length; i++) {
     var c = string.codeUnitAt(i);
     var flag = 0;
     if (c <= _ASCII_END) {
       flag = _ascii[c];
     }

     if (c <= _ASCII_END) {
       if (flag & _UPPER != 0) {
         return false;
       }
     } else {
       var s = string[i];
       if (s == s.toUpperCase()) {
         return false;
       }
     }
   }

   return true;
 }

 /**
  * Returns true if the string does not contain lower case letters; otherwise
  * false;
  *
  * Example:
  *     print(isUpperCase("CamelCase"));
  *     => false
  *
  *     print(isUpperCase("DART"));
  *     => true
  *
  *     print(isUpperCase(""));
  *     => false
  */
 bool isUpperCase(String string) {
   if (string == null) {
     throw new ArgumentError("string: $string");
   }

   if (string.length == 0) {
     return true;
   }

   var length = string.length;
   for (var i = 0; i < length; i++) {
     var c = string.codeUnitAt(i);
     var flag = 0;
     if (c <= _ASCII_END) {
       flag = _ascii[c];
     }

     if (c <= _ASCII_END) {
       if (flag & _LOWER != 0) {
         return false;
       }
     } else {
       var s = string[i];
       if (s == s.toLowerCase()) {
         return false;
       }
     }
   }

   return true;
 }

 /**
  * Returns the joined elements of the list if the list is not null; otherwise
  * null.
  *
  * Example:
  *     print(join(null));
  *     => null
  *
  *     print(join([1, 2]));
  *     => 12
  */
 String join(List list, [String separator = ""]) {
   if (list == null) {
     return null;
   }

   return list.join(separator);
 }

 /**
  * Returns a string with reversed order of characters.
  *
  * Example:
  *     print(reverse("hello"));
  *     => olleh
  */
 String reverse(String string) {
   if (string == null) {
     throw new ArgumentError("string: $string");
   }

   if (string.length < 2) {
     return string;
   }

   return new String.fromCharCodes(string.codeUnits.reversed);
 }

 /**
  * Returns true if the string starts with the lower case character; otherwise
  * false;
  *
  * Example:
  *     print(startsWithLowerCase("camelCase"));
  *     => true
  *
  *     print(startsWithLowerCase(""));
  *     => false
  */
 bool startsWithLowerCase(String string) {
   if (string == null) {
     throw new ArgumentError("string: $string");
   }

   if (string.length == 0) {
     return false;
   }

   var c = string.codeUnitAt(0);
   var flag = 0;
   if (c <= _ASCII_END) {
     flag = _ascii[c];
   }

   if (c <= _ASCII_END) {
     if (flag & _LOWER != 0) {
       return true;
     }
   } else {
     var s = string[0];
     if (s == s.toLowerCase()) {
       return true;
     }
   }

   return false;
 }

 /**
  * Returns true if the string starts with the upper case character; otherwise
  * false;
  *
  * Example:
  *     print(startsWithUpperCase("Dart"));
  *     => true
  *
  *     print(startsWithUpperCase(""));
  *     => false
  */
 bool startsWithUpperCase(String string) {
   if (string == null) {
     throw new ArgumentError("string: $string");
   }

   if (string.length == 0) {
     return false;
   }

   var c = string.codeUnitAt(0);
   var flag = 0;
   if (c <= _ASCII_END) {
     flag = _ascii[c];
   }

   if (c <= _ASCII_END) {
     if (flag & _UPPER != 0) {
       return true;
     }
   } else {
     var s = string[0];
     if (s == s.toUpperCase()) {
       return true;
     }
   }

   return false;
 }

 /**
  * Returns an unescaped printable string.
  *
  * Example:
  *     print(toPrintable("Hello 'world' \n"));
  *     => Hello 'world' \n
  */
 String toPrintable(String string) {
   if (string == null) {
     throw new ArgumentError("string: $string");
   }

   if (string.length == 0) {
     return string;
   }

   var sb = new StringBuffer();
   var i = 0;
   for (var c in string.runes) {
     if (c >= _C0_START && c <= _C0_END) {
       switch (c) {
         case 9:
           sb.write("\\t");
           break;
         case 10:
           sb.write("\\n");
           break;
         case 13:
           sb.write("\\r");
           break;
         default:
           sb.write(toUnicode(c));
       }

     } else if (_isPrintable(c)) {
       sb.write(string[i]);
     } else {
       sb.write(toUnicode(c));
     }

     i++;
   }

   return sb.toString();
 }

 /**
  * Returns an Unicode representation of the character code.
  *
  * Example:
  *     print(toUnicode(48));
  *     => \u0030
  */
 String toUnicode(int charCode) {
   if (charCode == null || charCode < 0 || charCode > _UNICODE_END) {
     throw new ArgumentError('charCode: $charCode');
   }

   var hex = charCode.toRadixString(16);
   var length = hex.length;
   if (length < 4) {
     hex = hex.padLeft(4, "0");
   }

   return '\\u$hex';
 }

 /**
  * Returns an underscored string.
  *
  * Example:
  *     print(underscore("DartVM DartCore"));
  *     => dart_vm dart_core
  */
 String underscore(String string) {
   if (string == null) {
     throw new ArgumentError("string: $string");
   }

   if (string.length == 0) {
     return string;
   }

   var length = string.length;
   var sb = new StringBuffer();
   var separate = false;
   for (var i = 0; i < length; i++) {
     var s = string[i];
     var c = s.codeUnitAt(0);
     var flag = 0;
     if (c <= _ASCII_END) {
       flag = _ascii[c];
     }

     if (separate && flag & _UPPER != 0) {
       sb.write("_");
       sb.write(s);
       separate = true;
     } else {
       if (flag & _ALPHA_NUM != 0) {
         separate = true;
       } else if (flag & _UNDERSCORE != 0 && separate) {
         separate = true;
       } else {
         separate = false;
       }

       sb.write(s);
     }
   }

   return sb.toString().toLowerCase();
 }

 SparseBoolList _generateBool(List<int> ranges) {
   var list = new SparseBoolList();
   var length = ranges.length;
   for (var i = 0; i < length; i += 2) {
     list.addGroup(new GroupedRangeList<bool>(ranges[i], ranges[i + 1], true));
   }

   return list;
 }

 // TODO: Optimize via table
 // TODO: Improve list of printable characters
 bool _isPrintable(int character) {
   switch (unicode.generalCategories[character]) {
     case unicode.CONTROL:
     case unicode.FORMAT:
     case unicode.LINE_SEPARATOR:
     case unicode.NOT_ASSIGNED:
     case unicode.PARAGRAPH_SEPARATOR:
     case unicode.PRIVATE_USE:
     case unicode.SURROGATE:
       return false;
     default:
       return true;
   }
 }
	part of strings;

	const int _ASCII_END = 0x7f;

	const int _ASCII_START = 0x0;

	const int _C0_END = 0x1f;

	const int _C0_START = 0x00;

	const int _UNICODE_END = 0x10ffff;

	const int _DIGIT = 0x1;

	const int _LOWER = 0x2;

	const int _UNDERSCORE = 0x4;

	const int _UPPER = 0x8;

	const int _ALPHA = _LOWER \| _UPPER;

	const int _ALPHA_NUM = _ALPHA \| _DIGIT;

	const int _VALID = _ALPHA_NUM \| _UNDERSCORE;

	final List<int> _ascii = <int>[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8,
	8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 4, 0, 2, 2, 2, 2,
	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 0, 0,
	0];

	/**
	* Returns a string in the form "UpperCamelCase" or "lowerCamelCase".
	*
	* Example:
	* print(camelize("dart_vm"));
	* => DartVm
	*/
	String camelize(String string, [bool lower = false]) {
	if (string == null) {
	throw new ArgumentError("string: $string");
	}

	if (string.length == 0) {
	return string;
	}

	string = string.toLowerCase();
	var capitlize = true;
	var length = string.length;
	var position = 0;
	var remove = false;
	var sb = new StringBuffer();
	for (var i = 0; i < length; i++) {
	var s = string[i];
	var c = s.codeUnitAt(0);
	var flag = 0;
	if (c <= _ASCII_END) {
	flag = _ascii[c];
	}

	if (capitlize && flag & _ALPHA != 0) {
	if (lower && position == 0) {
	sb.write(s);
	} else {
	sb.write(s.toUpperCase());
	}

	capitlize = false;
	remove = true;
	position++;
	} else {
	if (flag & _UNDERSCORE != 0) {
	if (!remove) {
	sb.write(s);
	remove = true;
	}

	capitlize = true;
	} else {
	if (flag & _ALPHA_NUM != 0) {
	capitlize = false;
	remove = true;
	} else {
	capitlize = true;
	remove = false;
	position = 0;
	}

	sb.write(s);
	}
	}
	}

	return sb.toString();
	}

	/**
	* Returns a string with capitalized first character.
	*
	* Example:
	* print(capitalize("dart"));
	* => Dart
	*/
	String capitalize(String string) {
	if (string == null) {
	throw new ArgumentError("string: $string");
	}

	if (string.length == 0) {
	return string;
	}

	return string[0].toUpperCase() + string.substring(1);
	}

	/**
	* Returns an escaped string.
	*
	* Example:
	* print(escape("Hello 'world' \n"));
	* => Hello \'world\' \n
	*/
	String escape(String string, [String encode(int charCode)]) {
	if (string == null) {
	throw new ArgumentError("string: $string");
	}

	if (string.length == 0) {
	return string;
	}

	if (encode == null) {
	encode = toUnicode;
	}

	var sb = new StringBuffer();
	var i = 0;
	for (var c in string.runes) {
	if (c >= _C0_START && c <= _C0_END) {
	switch (c) {
	case 9:
	sb.write("\\t");
	break;
	case 10:
	sb.write("\\n");
	break;
	case 13:
	sb.write("\\r");
	break;
	default:
	sb.write(encode(c));
	}

	} else if (c >= _ASCII_START && c <= _ASCII_END) {
	switch (c) {
	case 34:
	sb.write("\\\"");
	break;
	case 36:
	sb.write("\\\$");
	break;
	case 39:
	sb.write("\\\'");
	break;
	case 92:
	sb.write("\\\\");
	break;
	default:
	sb.write(string[i]);
	}

	} else if (_isPrintable(c)) {
	sb.write(string[i]);
	} else {
	sb.write(encode(c));
	}

	i++;
	}

	return sb.toString();
	}

	/**
	* Returns true if the string does not contain upper case letters; otherwise
	* false;
	*
	* Example:
	* print(isLowerCase("camelCase"));
	* => false
	*
	* print(isLowerCase("dart"));
	* => true
	*
	* print(isLowerCase(""));
	* => false
	*/
	bool isLowerCase(String string) {
	if (string == null) {
	throw new ArgumentError("string: $string");
	}

	if (string.length == 0) {
	return true;
	}

	var length = string.length;
	for (var i = 0; i < length; i++) {
	var c = string.codeUnitAt(i);
	var flag = 0;
	if (c <= _ASCII_END) {
	flag = _ascii[c];
	}

	if (c <= _ASCII_END) {
	if (flag & _UPPER != 0) {
	return false;
	}
	} else {
	var s = string[i];
	if (s == s.toUpperCase()) {
	return false;
	}
	}
	}

	return true;
	}

	/**
	* Returns true if the string does not contain lower case letters; otherwise
	* false;
	*
	* Example:
	* print(isUpperCase("CamelCase"));
	* => false
	*
	* print(isUpperCase("DART"));
	* => true
	*
	* print(isUpperCase(""));
	* => false
	*/
	bool isUpperCase(String string) {
	if (string == null) {
	throw new ArgumentError("string: $string");
	}

	if (string.length == 0) {
	return true;
	}

	var length = string.length;
	for (var i = 0; i < length; i++) {
	var c = string.codeUnitAt(i);
	var flag = 0;
	if (c <= _ASCII_END) {
	flag = _ascii[c];
	}

	if (c <= _ASCII_END) {
	if (flag & _LOWER != 0) {
	return false;
	}
	} else {
	var s = string[i];
	if (s == s.toLowerCase()) {
	return false;
	}
	}
	}

	return true;
	}

	/**
	* Returns the joined elements of the list if the list is not null; otherwise
	* null.
	*
	* Example:
	* print(join(null));
	* => null
	*
	* print(join([1, 2]));
	* => 12
	*/
	String join(List list, [String separator = ""]) {
	if (list == null) {
	return null;
	}

	return list.join(separator);
	}

	/**
	* Returns a string with reversed order of characters.
	*
	* Example:
	* print(reverse("hello"));
	* => olleh
	*/
	String reverse(String string) {
	if (string == null) {
	throw new ArgumentError("string: $string");
	}

	if (string.length < 2) {
	return string;
	}

	return new String.fromCharCodes(string.codeUnits.reversed);
	}

	/**
	* Returns true if the string starts with the lower case character; otherwise
	* false;
	*
	* Example:
	* print(startsWithLowerCase("camelCase"));
	* => true
	*
	* print(startsWithLowerCase(""));
	* => false
	*/
	bool startsWithLowerCase(String string) {
	if (string == null) {
	throw new ArgumentError("string: $string");
	}

	if (string.length == 0) {
	return false;
	}

	var c = string.codeUnitAt(0);
	var flag = 0;
	if (c <= _ASCII_END) {
	flag = _ascii[c];
	}

	if (c <= _ASCII_END) {
	if (flag & _LOWER != 0) {
	return true;
	}
	} else {
	var s = string[0];
	if (s == s.toLowerCase()) {
	return true;
	}
	}

	return false;
	}

	/**
	* Returns true if the string starts with the upper case character; otherwise
	* false;
	*
	* Example:
	* print(startsWithUpperCase("Dart"));
	* => true
	*
	* print(startsWithUpperCase(""));
	* => false
	*/
	bool startsWithUpperCase(String string) {
	if (string == null) {
	throw new ArgumentError("string: $string");
	}

	if (string.length == 0) {
	return false;
	}

	var c = string.codeUnitAt(0);
	var flag = 0;
	if (c <= _ASCII_END) {
	flag = _ascii[c];
	}

	if (c <= _ASCII_END) {
	if (flag & _UPPER != 0) {
	return true;
	}
	} else {
	var s = string[0];
	if (s == s.toUpperCase()) {
	return true;
	}
	}

	return false;
	}

	/**
	* Returns an unescaped printable string.
	*
	* Example:
	* print(toPrintable("Hello 'world' \n"));
	* => Hello 'world' \n
	*/
	String toPrintable(String string) {
	if (string == null) {
	throw new ArgumentError("string: $string");
	}

	if (string.length == 0) {
	return string;
	}

	var sb = new StringBuffer();
	var i = 0;
	for (var c in string.runes) {
	if (c >= _C0_START && c <= _C0_END) {
	switch (c) {
	case 9:
	sb.write("\\t");
	break;
	case 10:
	sb.write("\\n");
	break;
	case 13:
	sb.write("\\r");
	break;
	default:
	sb.write(toUnicode(c));
	}

	} else if (_isPrintable(c)) {
	sb.write(string[i]);
	} else {
	sb.write(toUnicode(c));
	}

	i++;
	}

	return sb.toString();
	}

	/**
	* Returns an Unicode representation of the character code.
	*
	* Example:
	* print(toUnicode(48));
	* => \u0030
	*/
	String toUnicode(int charCode) {
	if (charCode == null \|\| charCode < 0 \|\| charCode > _UNICODE_END) {
	throw new ArgumentError('charCode: $charCode');
	}

	var hex = charCode.toRadixString(16);
	var length = hex.length;
	if (length < 4) {
	hex = hex.padLeft(4, "0");
	}

	return '\\u$hex';
	}

	/**
	* Returns an underscored string.
	*
	* Example:
	* print(underscore("DartVM DartCore"));
	* => dart_vm dart_core
	*/
	String underscore(String string) {
	if (string == null) {
	throw new ArgumentError("string: $string");
	}

	if (string.length == 0) {
	return string;
	}

	var length = string.length;
	var sb = new StringBuffer();
	var separate = false;
	for (var i = 0; i < length; i++) {
	var s = string[i];
	var c = s.codeUnitAt(0);
	var flag = 0;
	if (c <= _ASCII_END) {
	flag = _ascii[c];
	}

	if (separate && flag & _UPPER != 0) {
	sb.write("_");
	sb.write(s);
	separate = true;
	} else {
	if (flag & _ALPHA_NUM != 0) {
	separate = true;
	} else if (flag & _UNDERSCORE != 0 && separate) {
	separate = true;
	} else {
	separate = false;
	}

	sb.write(s);
	}
	}

	return sb.toString().toLowerCase();
	}

	SparseBoolList _generateBool(List<int> ranges) {
	var list = new SparseBoolList();
	var length = ranges.length;
	for (var i = 0; i < length; i += 2) {
	list.addGroup(new GroupedRangeList<bool>(ranges[i], ranges[i + 1], true));
	}

	return list;
	}

	// TODO: Optimize via table
	// TODO: Improve list of printable characters
	bool _isPrintable(int character) {
	switch (unicode.generalCategories[character]) {
	case unicode.CONTROL:
	case unicode.FORMAT:
	case unicode.LINE_SEPARATOR:
	case unicode.NOT_ASSIGNED:
	case unicode.PARAGRAPH_SEPARATOR:
	case unicode.PRIVATE_USE:
	case unicode.SURROGATE:
	return false;
	default:
	return true;
	}
	}