Big-Data-HPC-Platform/docs/ECLLanguageReference/ECLR_mods/Value-Boolean.xml

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<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
<sect1 id="BOOLEAN" role="nobrk">
  <title>BOOLEAN</title>

  <para><emphasis role="bold">BOOLEAN<indexterm>
      <primary>BOOLEAN</primary>
    </indexterm><indexterm>
      <primary>BOOLEAN value type</primary>
    </indexterm></emphasis></para>

  <para>A Boolean true/false value. <emphasis
  role="bold">TRUE</emphasis><indexterm>
      <primary>TRUE</primary>
    </indexterm> and <emphasis role="bold">FALSE<indexterm>
      <primary>FALSE</primary>
    </indexterm></emphasis> are reserved ECL keywords; they are Boolean
  constants that may be used to compare against a BOOLEAN type. When BOOLEAN
  is used in a RECORD structure, a single-byte integer containing one (1) or
  zero (0) is output.</para>

  <para>Example:</para>

  <programlisting>BOOLEAN MyBoolean := SomeAttribute &gt; 10;
        // declares MyBoolean a BOOLEAN Attribute
     
BOOLEAN MyBoolean(INTEGER p) := p &gt; 10;
        // MyBoolean takes an INTEGER parameter

BOOLEAN Typtrd := trades.trd_type = 'R';
        // Typtrd is a Boolean attribute, likely to be used as a filter</programlisting>

  <para>See Also: <link linkend="TRUE_FALSE">TRUE/FALSE</link></para>
</sect1>