pascalabcnet/PABCNetHelp/LangGuide/Operators/with.html

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<H1>Îïåðàòîð with</H1>
Îïåðàòîð <b><code>with</code></b> ïîçâîëÿåò ñîêðàòèòü îáðàùåíèå
ê ïîëÿì çàïèñè, à òàêæå ê ïîëÿì, ìåòîäàì è ñâîéñòâàì îáúåêòà. Îí èìååò âèä:<blockquote>
<p><code><b>with</b> </code> <code class="codeit">èìÿ
çàïèñè èëè îáúåêòà</code><code> <b>do</b> </code>
<code class="codeit">îïåðàòîð</code></p>
</blockquote>
<p>èëè</p><blockquote>
<p><code><b>with</b> </code> <code class="codeit">ñïèñîê èìåí</code><code> <b>do</b> </code>
<code class="codeit">îïåðàòîð</code></p>
</blockquote>
<p>Âñþäó âíóòðè îïåðàòîðà ìîæíî îïóñêàòü èìÿ çàïèñè ïðè
îáðàùåíèè ê ïîëþ óêàçàííîé çàïèñè èëè èìÿ îáúåêòà ïðè îáðàùåíèè ê ïîëþ, ìåòîäó
èëè ñâîéñòâó óêàçàííîãî îáúåêòà. Íàïðèìåð, ïóñòü îïèñàíà
ïåðåìåííàÿ </p>
<blockquote>
<p><code><b>var</b> <br>
&nbsp; DateOfBirthday =<b> record</b><br>
&nbsp;&nbsp;&nbsp; Day: Integer;<br>
&nbsp;&nbsp;&nbsp; Month: Integer;<br>
&nbsp;&nbsp;&nbsp; Year: Integer;<br>
&nbsp; <b>end</b>;</code></p>
</blockquote>
<p>Òîãäà ïðèñâàèâàíèå çíà÷åíèé åå ïîëÿì áåç èñïîëüçîâàíèÿ
îïåðàòîðà <b><code>with</code></b> èìååò âèä:</p>
<blockquote>
<p><code>DateOfBirthday.Day := 23;<br>
DateOfBirthday.Month := 2;<br>
DateOfBirthday.Year := 1965;</code></p>
</blockquote>
<p>Èñïîëüçîâàíèå îïåðàòîðà <code><b>with</b></code> ïîçâîëÿåò ñîêðàòèòü
ïðåäûäóùóþ çàïèñü:</p>
<blockquote>
<p><code><b>with</b> DateOfBirthday <b>do</b><br>
<b>begin</b><br>
&nbsp; Day := 23;<br>
&nbsp; Month := 2;<br>
&nbsp; Year := 1965;<br>
<b>end</b>;</code></p>
</blockquote>
<p>Åñëè âíåøíÿÿ ïåðåìåííàÿ èìååò òî æå èìÿ, ÷òî è ïîëå (ìåòîä, ñâîéñòâî), òî
ïðåäïî÷òåíèå îòäàåòñÿ ïîëþ (ìåòîäó, ñâîéñòâó). Ïðè íàëè÷èè âëîæåííûõ îïåðàòîðîâ
<code><b>with</b></code> âíà÷àëå ïðåäïðèíèìàåòñÿ ïîïûòêà ðàññìàòðèâàòü ïåðåìåííóþ êàê ïîëå çàïèñè
èëè îáúåêòà ñàìîãî âíóòðåííåãî îïåðàòîðà <code><b>with</b></code>, çàòåì íåïîñðåäñòâåííî îáúåìëþùåãî
åãî îïåðàòîðà <code><b>with</b></code> è ò.ä. Åñëè îïåðàòîð
<code><b>with</b></code> &nbsp;ñîäåðæèò ñïèñîê îáúåêòîâ,
òî îíè ðàññìàòðèâàåòñÿ ñïðàâà íàëåâî. Íàïðèìåð, åñëè èìåþòñÿ îïèñàíèÿ </p>
<blockquote>
<p><code><b>var</b> <br>
&nbsp; x,y,z: integer;<br>
&nbsp; a: <b>record</b><br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; x,y: integer;<br>
&nbsp; <b>&nbsp;&nbsp; end</b>;<br>
&nbsp; b: <b>record</b><br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; x: integer;<br>
&nbsp; <b>&nbsp;&nbsp; end</b>;</code></blockquote>
<p>òî ôðàãìåíò ïðîãðàììû</p>
<blockquote><code><b>with</b> a,b <b>do</b><br>
<b>begin</b><br>
&nbsp; x := 1; <br>
&nbsp; y := 2;<br>
&nbsp; z := 3;&nbsp; <br>
<b>end</b>;</code></blockquote>
<p>ýêâèâàëåíòåí ôðàãìåíòó</p>
<blockquote><code><b>with</b> a <b>do</b><br>
&nbsp;<b>with</b> b <b>do</b><br>
<b>&nbsp;begin</b><br>
&nbsp;&nbsp; x := 1; <br>
&nbsp;&nbsp; y := 2;<br>
&nbsp;&nbsp; z := 3;&nbsp; <br>
<b>&nbsp;end</b>;</code></blockquote>
<p>à òàêæå ôðàãìåíòó </p>
<blockquote><p><code>b.x:=1; <br>
a.y:=2;<br>
z:=3;</code></p>
</blockquote>
<p>Îïåðàòîð with óñòàðåë è ñåé÷àñ ïðàêòè÷åñêè íå èñïîëüçóåòñÿ.</p>
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