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  13. <title>avram - a virtual machine code interpreter: 2.7.4.1 Syntax</title>
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  39. <a name="Syntax"></a>
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  57. <a name="Syntax-1"></a>
  58. <h4 class="subsubsection">2.7.4.1 Syntax</h4>
  59. <p><code>silly</code> has no reserved words, but it has equals signs, commas and
  60. parentheses built in. A concise but ambiguous grammar for it can be given
  61. as follows.
  62. <a name="index-syntax"></a>
  63. <a name="index-grammar"></a>
  64. </p><table><tr><td>&nbsp;</td><td><pre class="display">
  65. <var>program</var> ::= <var>declaration</var>*
  66. <var>declaration</var> ::= <var>identifier</var> <code>=</code> <var>expression</var>
  67. </pre></td></tr></table>
  68. <a name="index-precedence"></a>
  69. <a name="index-operator-precedence"></a>
  70. <p>The real grammar is consistent with this one but enforces right
  71. associativity for binary operations and higher precedence for juxtaposition
  72. without intervening white space.
  73. </p>
  74. <p>The declaration of any identifier must be unique and must precede its
  75. occurrence in any expression. Hence, cyclic dependences between
  76. declarations and &ldquo;recursive&rdquo; declarations are not allowed.
  77. </p>
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