luke
/
klayout
mirror of https://github.com/KLayout/klayout.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Expressions doc.

This commit is contained in:
Matthias Koefferlein 2026-06-13 21:49:20 +02:00
parent 1f63aaabf5
commit d09eb21096
1 changed files with 17 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

32
src/doc/doc/about/expressions.xml
View File

@ -79,11 +79,12 @@ Box.new(-10, 0, 90, 60).width
The "nil" value shortcuts numerical expressions the following way:
</p>
<pre>
nil + x -> nil
x + nil -> x
nil + nil -> nil
</pre>
<table>
<tr><th>Expression</th><th>Result</th></tr>
<tr><td><tt>nil + x</tt></td><td><tt>nil</tt></td></tr>
<tr><td><tt>x + nil</tt></td><td><tt>x</tt></td></tr>
<tr><td><tt>nil + nil</tt></td><td><tt>nil</tt></td></tr>
</table>
<p>
The same applies to the other binary operators "*", "/", "-", "&amp;" "|", "&lt;&lt; and "&gt;&gt;".
@ -97,16 +98,17 @@ nil + nil -> nil
The logical binary operators "||" and "&amp;&amp;" behave this way:
</p>
<pre>
x || y -> x if x is not "nil" or "false", y otherwise
x || nil -> x
nil || x -> x
nil || nil -> nil
x &amp;&amp; y -> y if x is not "nil" or "false", x otherwise
x &amp;&amp; nil -> nil
nil &amp;&amp; x -> nil
nil &amp;&amp; nil -> nil
</pre>
<table>
<tr><th>Expression</th><th>Result</th></tr>
<tr><td><tt>x || y</tt></td><td><tt>x if x is not "nil" or "false", y otherwise</tt></td></tr>
<tr><td><tt>x || nil</tt></td><td><tt>x</tt></td></tr>
<tr><td><tt>nil || x</tt></td><td><tt>x</tt></td></tr>
<tr><td><tt>nil || nil</tt></td><td><tt>nil</tt></td></tr>
<tr><td><tt>x &amp;&amp; y</tt></td><td><tt>y if x is not "nil" or "false", x otherwise</tt></td></tr>
<tr><td><tt>x &amp;&amp; nil</tt></td><td><tt>nil</tt></td></tr>
<tr><td><tt>nil &amp;&amp; x</tt></td><td><tt>nil</tt></td></tr>
<tr><td><tt>nil &amp;&amp; nil</tt></td><td><tt>nil</tt></td></tr>
</table>
<h2>Constants</h2>