<HTML><TITLE>runarray Specification Sheet</TITLE><H1>runarray Specification Sheet</H1> <HR>Portable Object Compiler (c) 1997,98,99,03.  All Rights Reserved.<P><H1>RunArray</H1><B>Inherits from:</B> Cltn<P><B>Maturity Index:</B> Experimental<P><H2>Class Description</H2>This class is used by the <B>Text</B> class, to associate lists of <B>TextAttribute</B> instances, to segments of characters in a string (slices of text with the same formatting properties, called <I>runs</I>).<P><H2>Accessing</H2>A <B>RunArray</B> is <I>not</I> indexed by segment number.<P>Rather, it is indexed by character offsets : the message <B>at:</B> or <B>runLengthAt:</B> takes a character offset as argument, and translates this offset to a segment offset (the segment to which the character belongs) and returns the attributes or segment length, for that segment.<P>The <B>size</B> of a <B>RunArray</B> is the largest character offset plus one;it is not the number of segments.<P><H2>Method types</H2><H3><B>Creation</B></H3><UL><LI><A HREF="#2">new</A></LI><LI><A HREF="#3">free</A></LI></UL><H3><B>Accessing</B></H3><UL><LI><A HREF="#4">values</A></LI><LI><A HREF="#5">runs</A></LI><LI><A HREF="#7">at:</A></LI><LI><A HREF="#8">runLengthAt:</A></LI><LI><A HREF="#9">size</A></LI><LI><A HREF="#14">addAttribute:from:size:</A></LI><LI><A HREF="#16">at:insert:count:</A></LI><LI><A HREF="#17">deleteFrom:to:</A></LI><LI><A HREF="#18">concat:</A></LI><LI><A HREF="#19">coalesce</A></LI></UL><H3><B>Printing</B></H3><UL><LI><A HREF="#20">printOn:</A></LI></UL><H2>Methods</H2><H3><A NAME="2">new</A></H3><BLOCKQUOTE>+<B>new</B></BLOCKQUOTE>Creates an empty RunArray collection.<P><H3><A NAME="3">free</A></H3><BLOCKQUOTE>-<B>free</B></BLOCKQUOTE><H3><A NAME="4">values</A></H3><BLOCKQUOTE>-<B>values</B></BLOCKQUOTE>Returns a collection of OrdCltn instances (each element being a list of <B>TextAttribute</B> instances).<P><H3><A NAME="5">runs</A></H3><BLOCKQUOTE>-<B>runs</B></BLOCKQUOTE>Returns the run array (array of <I>int</I>).<P><H3><A NAME="7">at:</A></H3><BLOCKQUOTE>-<B>at</B>:(unsigned)<I>i</I></BLOCKQUOTE>Returns a collection of TextAttributes for the <I>i</I>-th character.<P>This method translates a character offset into a segment number.  The segment number is cached so that a subsequent call to <B>at:</B> or <B>runLengthAt:</B> doesn't have to recompute it.<P><H3><A NAME="8">runLengthAt:</A></H3><BLOCKQUOTE>- (unsigned)<B>runLengthAt</B>:(unsigned)<I>i</I></BLOCKQUOTE>Returns the number of remaining characters in the string segment to which the character at position <I>i</I> belongs.  If <I>i</I> is the first character of a run, this method returns the size of the run.  Otherwise it returns the size minus the index of character in the run.<P><H3><A NAME="9">size</A></H3><BLOCKQUOTE>- (unsigned)<B>size</B></BLOCKQUOTE>Returns the size of the RunArray, which is the same as the size of the String instance for this RunArray object.<P>The number of runs can be obtained by sending a <B>size</B> message to the object returned by <B>values</B>.<P><H3><A NAME="14">addAttribute:from:size:</A></H3><BLOCKQUOTE>-<B>addAttribute</B>:<I>attrib</I><B>from</B>:(unsigned)<I>p</I><B>size</B>:(unsigned)<I>s</I></BLOCKQUOTE>Adds <I>attrib</I> to the attribute lists for the <I>s</I> characters from position <I>p</I>.<P><B>Note:</B> This method is optimized for adding at the end of the RunArray.<P><H3><A NAME="16">at:insert:count:</A></H3><BLOCKQUOTE>-<B>at</B>:(unsigned)<I>anOffset</I><B>insert</B>:(char*)<I>aString</I><B>count</B>:(int)<I>n</I></BLOCKQUOTE><H3><A NAME="17">deleteFrom:to:</A></H3><BLOCKQUOTE>-<B>deleteFrom</B>:(unsigned)<I>p</I><B>to</B>:(unsigned)<I>q</I></BLOCKQUOTE><H3><A NAME="18">concat:</A></H3><BLOCKQUOTE>-<B>concat</B>:<I>b</I></BLOCKQUOTE><H3><A NAME="19">coalesce</A></H3><BLOCKQUOTE>-<B>coalesce</B></BLOCKQUOTE>Merges adjacent lists of TextAttribute instances, by testing whether they are equal (in the sense of <B>TextAttribute</B>'s <B>isEqual</B> method).<P><H3><A NAME="20">printOn:</A></H3><BLOCKQUOTE>-<B>printOn</B>:(IOD)<I>aFile</I></BLOCKQUOTE>Prints the RunArray values.<P>