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Convert EBCDIC string to Unicode constant, including character encoding (String class)


This intrinsic function converts an EBCDIC string, which may include XML character and entity references, to a Unicode string. The function also converts XML style hexadecimal character references, XHTML entity references, and '&' references to the represented Unicode character. Since in use the method acts like a Unicode constant, it is also documented with the Constant methods.

The U method is available as of Sirius Mods version 7.3.

Syntax

%unicode = string:U

Syntax terms

%unicode A Unicode string variable to receive the Unicode encoding of the method object string.
string A constant character string value, which may include an XML-style hexadecimal character reference or an XHTML entity reference. That is, string may contain an ampersand (&) in the following cases: *As the substring '&'. This substring is converted to a single ampersand character. *At the start of a hexadecimal character reference (for example, the eight characters '“' for the Unicode "Left double quotation mark"). The character reference is converted to the referenced character. *As of Sirius Mods version 7.6, an XHTML entity reference (for example, the six characters ' ' for the "non-breaking-space" character). The entity reference is converted to the referenced character. A decimal character reference (for example, ¬) is not allowed.

Usage notes

  • The U method is a compile-time-only equivalent of the EbcdicToUnicode method of the intrinsic String class (with its CharacterDecode argument implicitly set to 'True').
  • Using the U method (or EbcdicToUnicode) is necessary for converting to type Unicode if the string you want to convert may contain a hexadecimal character reference. Such a reference cannot be meaningfully assigned to a Unicode variable otherwise, whereas keyboard-available characters can simply be assigned directly to a Unicode variable without character reference and without conversion by U.
  • You can find the list of XHTML entities on the Internet at the following URL:
   http://www.w3.org/TR/xhtml1/dtds.html#h-A2

Example

The first Print statement below displays a plus sign (+); the second Print displays a copyright sign (©); the third displays '2122':

   %p Unicode Initial('+')
   Print %p
   * Entity for copyright symbol:
   %copy Unicode Initial('©':U)
   Print %copy
   * Constant for trademark symbol:
   %tm Unicode Initial('™':U)
   Print %tm:UnicodeToUtf16:StringToHex

Note

Simply specifying 'Print %tm' in the the third Print statement above (or its equivalent 'Print %tm:UnicodeToEbcdic') would attempt to translate to EBCDIC and fail because the Unicode trademark character does not translate to a valid EBCDIC character. But the UnicodeToUtf16 method can convert the Unicode variable to a byte-stream Longstring, which the StringToHex method converts to its hex representation.

See also

List of intrinsic String methods