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Boolean values: Difference between revisions
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=={{header|Java}}==
Java has <tt>true</tt> and <tt>false</tt> keywords, representing the only values of type <tt>boolean</tt>. There are also object wrappers <tt>Boolean.TRUE</tt> and <tt>Boolean.FALSE</tt>, of type <tt>Boolean</tt> which may be un-boxed into <tt>boolean</tt>s (auto-unboxed in Java 1.5+). There are no automatic conversions from any other types into <tt>boolean</tt>, and it is a compile-time error to use any type other than <tt>boolean</tt> or <tt>Boolean</tt> in a place that expects a <tt>boolean</tt> (e.g. if-statement condition, while-statement condition, operand of a logical operator, etc.).
=={{header|JavaScript}}==
The Boolean type has two values: <code>true</code> and <code>false</code>
The following table shows the result of type conversions to boolean:
* Undefined: any undefined value is converted to <code>false</code>
* Null: <code>false</code>
* Number: the numbers <code>0</code>, <code>-0</code>, <code>NaN</code> are <code>false</code>; otherwise <code>true</code>
* String: the empty (zero-length) string is <code>false</code>; otherwise <code>true</code>
* Object: any object is converted to <code>true</code>
(source: [http://www.ecma-international.org/publications/standards/Ecma-262.htm ECMAScript Language Reference])
=={{header|Logo}}==
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