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POWhat's the reason high-level languages like C#/Java mask the bit shift count operand?
 

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  1. POWhat's the reason high-level languages like C#/Java mask the bit shift count operand?
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    <p>This is more of a language design rather than a programming question.</p> <p>The following is an excerpt from <a href="http://java.sun.com/docs/books/jls/third_edition/html/expressions.html#15.19" rel="nofollow noreferrer">JLS 15.19 Shift Operators</a>:</p> <blockquote> <p>If the promoted type of the left-hand operand is <code>int</code>, only the five lowest-order bits of the right-hand operand are used as the shift distance.</p> <p>If the promoted type of the left-hand operand is <code>long</code>, then only the six lowest-order bits of the right-hand operand are used as the shift distance.</p> </blockquote> <p>This behavior is also <a href="http://msdn.microsoft.com/en-us/library/aa691377%28VS.71%29.aspx" rel="nofollow noreferrer">specified in C#</a>, and while I'm not sure if it's in the official spec for Javascript (if there's one), it's also true based on my own test at least.</p> <p>The consequence is that the following is true:</p> <pre><code>(1 &lt;&lt; 32) == 1 </code></pre> <p>I understand that this specification is probably "inspired" by the fact that the underlying hardware only takes 5 bits for the count operand when shifting 32-bit values (and 6 bits for 64-bit), and I can understand such behavior specified at the JVM level for example, but why would high level languages such as C# and Java retain this rather low-level behavior? Shouldn't they provide a more abstract view beyond the hardware implementation and behave more intuitively? (Even better if they can take a negative count to mean to shift in the OTHER direction!)</p>
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