U (String function): Difference between revisions

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{{Template:String:U subtitle}}
{{Template:String:U subtitle}}


The <var>U</var> [[Intrinsic classes|intrinsic]] method 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 <b>'&amp;amp;'</b> 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 <var>U</var> [[Intrinsic classes|intrinsic]] method 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 <b>'&amp;amp;'</b> references to the represented Unicode character. Since in use the method acts like a Unicode constant, it is also documented with the [[Constant methods]].


==Syntax==
==Syntax==
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<ul><li><var>U</var> is a compile-time-only equivalent of the [[EbcdicToUnicode (String function)|EbcdicToUnicode]] method of the intrinsic <var>String</var> class (with its CharacterDecode argument implicitly set to <code>'True'</code>).
<ul><li><var>U</var> is a compile-time-only equivalent of the [[EbcdicToUnicode (String function)|EbcdicToUnicode]] method of the intrinsic <var>String</var> class (with its CharacterDecode argument implicitly set to <code>'True'</code>).
<li>Using the <var>U</var> 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 <var>U</var>.
<li>Using the <var>U</var> 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 <var>U</var>.
<li>You can find the list of XHTML entities on the Internet at the following <var>U</var>RL:
<p class="code">http://www.w3.org/TR/xhtml1/dtds.html#h-A2
</p>
<li>The <var>U</var> method is available as of <var class="product">[[Sirius Mods]]</var> version 7.3.</ul>
<li>The <var>U</var> method is available as of <var class="product">[[Sirius Mods]]</var> version 7.3.</ul>


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<p class="code">%tm Unicode Initial('&amp;#x2122;':U)
<p class="code">%tm Unicode Initial('&amp;#x2122;':U)
Print %tm:UnicodeToUtf16:StringToHex
Print %tm:UnicodeToUtf16:StringToHex
</p></ol>
</p>
 
===Note===
===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 string, which the StringToHex method converts to its hex representation.
Simply specifying <code>'print %tm'<code> in the the third Print example above (or its equivalent <code>'print %tm:UnicodeToEbcdic'</code>) 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 string, which the StringToHex method converts to its hex representation.</ol>


==See also==
==See also==
<ul><li>You can find the list of XHTML entities on the Internet at the following <var>U</var>RL:
<p class="code">http://www.w3.org/TR/xhtml1/dtds.html#h-A2
</p></ul>
{{Template:String:U footer}}
{{Template:String:U footer}}

Revision as of 22:02, 2 February 2011

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


The U intrinsic method 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 '&amp;' references to the represented Unicode character. Since in use the method acts like a Unicode constant, it is also documented with the Constant methods.

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 '&amp;'. This substring is converted to a single ampersand ('&') character.
  • At the start of a hexadecimal character reference (for example, the eight characters '&#x201C;' 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 '&nbsp;' for the "non-breaking-space" character). The entity reference is converted to the referenced character.
A decimal character reference (for example, &#172;) is not allowed.

Usage notes

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

Examples

  1. 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

  2. Entity for copyright symbol:

    %copy Unicode Initial('&copy;':U) Print %copy

  3. Constant for trademark symbol:

    %tm Unicode Initial('&#x2122;':U) Print %tm:UnicodeToUtf16:StringToHex

    Note

    Simply specifying 'print %tm' in the the third Print example 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 string, which the StringToHex method converts to its hex representation.

See also