Revision 118699 of Constants

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<h3 name="Constants"> Constants </h3>
<p>You can create a read-only, named constant with the <code><a href="en/Core_JavaScript_1.5_Reference/Statements/const">const</a></code> keyword. The syntax of a constant identifier is the same as for a variable identifier: it must start with a letter or underscore and can contain alphabetic, numeric, or underscore characters.
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<pre class="eval">const prefix = '212';
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<p>A constant cannot change value through assignment or be re-declared while the script is running.
</p><p>The scope rules for constants are the same as those for variables, except that the <code>const</code> keyword is always required, even for global constants. If the keyword is omitted, the identifier is assumed to represent a variable.
</p><p>You cannot declare a constant with the same name as a function or variable in the same scope. For example:
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<pre class="eval">// THIS WILL CAUSE AN ERROR
function f() {};
const f = 5;

// THIS WILL CAUSE AN ERROR ALSO
function f() {
  const g = 5;
  var g;

  //statements
}
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<p>{{ PreviousNext("Core_JavaScript_1.5_Guide:Variables", "Core_JavaScript_1.5_Guide:Literals") }}
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