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<TITLE>Boolean Operations -- Python library reference</TITLE>
Next: <A HREF="../c/comparisons" TYPE="Next">Comparisons</A>
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<H2>2.1.2. Boolean Operations</H2>
These are the Boolean operations, ordered by ascending priority:
<DL>
<DT><I>Operation</I><DD><I>Result</I> --- <I>Notes</I>
<P>
<DT><CODE><VAR>x</VAR> or <VAR>y</VAR></CODE><DD>if <VAR>x</VAR> is false, then <VAR>y</VAR>, else <VAR>x</VAR> --- (1)
<DT><CODE><VAR>x</VAR> and <VAR>y</VAR></CODE><DD>if <VAR>x</VAR> is false, then <VAR>x</VAR>, else <VAR>y</VAR> --- (1)
<DT><CODE>not <VAR>x</VAR></CODE><DD>if <VAR>x</VAR> is false, then <CODE>1</CODE>, else <CODE>0</CODE> --- (2)
</DL>
Notes:
<P>
<DL>
<DT><B>(1)</B><DD>These only evaluate their second argument if needed for their outcome.
<P>
<DT><B>(2)</B><DD>`<SAMP>not</SAMP>' has a lower priority than non-Boolean operators, so e.g.
<CODE>not a == b</CODE> is interpreted as <CODE>not(a == b)</CODE>, and
<CODE>a == not b</CODE> is a syntax error.
<P>
</DL>