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Docs: LazUtils/lazutf8. Adds UTF8CodepointCount topics for changes in c8a1f93a,

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dsiders 2024-08-29 17:01:04 +01:00
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docs/xml/lazutils/lazutf8.xml
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@ -632,6 +632,70 @@ Even faster UTF-8 character counting
<short>Number of byte values in the UTF-8-encoded string.</short>
</element>
<element name="UTF8CodepointCount">
<short>
Gets the number of UTF-8-encoded codepoints in the specified value.
</short>
<descr>
<p>
<var>UTF8CodepointCount</var> is an overloaded <var>PtrInt</var> function used
to determine the number of UTF-8 codepoints found in the specified value. The
overloaded variants allow the value to be specified using either the String or
the PChar type.
</p>
<p>
UTF8CodepointCount iterates over the byte values in the s or p arguments, and
increments the return value when a valid UTF-8 codepoint is found. Valid
codepoints include those represented by combining character combinations.
UTF8CodepointLen (in system.pp) is called to the get the size for each
of the UTF-8 codepoints. The process is repeated until all of the bytes in the
input value have been examined, or a codepoint with a length of zero (0) is encountered.
</p>
<p>
The return value is zero (0) if the s or p arguments are empty, or when the
ByteCount argument is zero (0).
</p>
</descr>
<version>
Added in LazUtils version 4.0. (c8a1f93a)
</version>
<notes>
<note>
I wrote a test application to compare the results for UTF8Length and
UTF8CodepointCount. They return exactly the same values for the UTF-8 strings I
cribbed from the Unicode web site.
So basically, why is this routine needed?
</note>
</notes>
<seealso>
<link id="UTF8CodepointSize"/>
<link id="UTF8Length"/>
<link id="UTF8LengthFast"/>
<link id="UTF8CharacterLength"/>
<link id="#rtl.system.UTF8CodepointLen">UTF8CodepointLen</link>
</seealso>
</element>
<element name="UTF8CodepointCount.Result">
<short>
Pointer to the Integer value with the number of codepoints including combining characters.
</short>
</element>
<element name="UTF8CodepointCount.s">
<short>
String with the codepoints examined in the routine.
</short>
</element>
<element name="UTF8CodepointCount.p">
<short>
PChar type with the codepoints examined in the routine.
</short>
</element>
<element name="UTF8CodepointCount.ByteCount">
<short>
Number of bytes in the PChar value.
</short>
</element>
<element name="UTF8CodepointToUnicode">
<short>
Converts a UTF-8-encoded character to its unique Unicode U+XXXX character