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<h1>Grammar</h1>
<h2 id="ebnf">EBNF</h2>
<div class="highlight"><pre><span></span><code><span class="k">schema </span><span class="o">=</span> <span class="k">include</span><span class="err">*</span> <span class="p">(</span> <span class="k">namespace_decl </span><span class="p">|</span> <span class="k">type_decl </span><span class="p">|</span> <span class="k">enum_decl </span><span class="p">|</span> <span class="k">root_decl </span><span class="p">|</span>
<span class="k">file_extension_decl </span><span class="p">|</span> <span class="k">file_identifier_decl </span><span class="p">|</span>
<span class="k">attribute_decl </span><span class="p">|</span> <span class="k">rpc_decl </span><span class="p">|</span> <span class="k">object </span><span class="p">)</span><span class="err">*</span>
<span class="k">include </span><span class="err">=</span> <span class="err">`</span><span class="k">include</span><span class="err">`</span> <span class="k">string_constant </span><span class="err">`</span><span class="p">;</span><span class="err">`</span>
<span class="k">namespace_decl </span><span class="o">=</span> <span class="err">`</span><span class="k">namespace</span><span class="err">`</span> <span class="k">ident </span><span class="p">(</span> <span class="err">`</span><span class="p">.</span><span class="err">`</span> <span class="k">ident </span><span class="err">)*</span> <span class="err">`;`</span>
<span class="k">attribute_decl </span><span class="o">=</span> <span class="err">`</span><span class="k">attribute</span><span class="err">`</span> <span class="k">ident </span><span class="p">|</span> <span class="err">`</span><span class="s2">&quot;` ident `&quot;</span><span class="err">`</span> <span class="err">`</span><span class="p">;</span><span class="err">`</span>
<span class="k">type_decl </span><span class="o">=</span> <span class="p">(</span> <span class="err">`</span><span class="k">table</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">struct</span><span class="err">`</span> <span class="p">)</span> <span class="k">ident metadata </span><span class="err">`</span><span class="p">{</span><span class="err">`</span> <span class="k">field_decl</span><span class="err">+</span> <span class="err">`</span><span class="p">}</span><span class="err">`</span>
<span class="k">enum_decl </span><span class="err">=</span> <span class="p">(</span> <span class="err">`</span><span class="k">enum</span><span class="err">`</span> <span class="k">ident </span><span class="err">`:`</span> <span class="k">type </span><span class="p">|</span> <span class="err">`</span><span class="k">union</span><span class="err">`</span> <span class="k">ident </span><span class="p">)</span> <span class="k">metadata </span><span class="err">`</span><span class="p">{</span><span class="err">`</span>
<span class="k">commasep</span><span class="p">(</span> <span class="k">enumval_decl </span><span class="p">)</span> <span class="err">`</span><span class="p">}</span><span class="err">`</span>
<span class="k">root_decl </span><span class="err">=</span> <span class="err">`</span><span class="k">root_type</span><span class="err">`</span> <span class="k">ident </span><span class="err">`</span><span class="p">;</span><span class="err">`</span>
<span class="k">field_decl </span><span class="o">=</span> <span class="k">ident </span><span class="err">`:`</span> <span class="k">type </span><span class="p">[</span> <span class="err">`=`</span> <span class="k">scalar </span><span class="p">]</span> <span class="k">metadata </span><span class="err">`</span><span class="p">;</span><span class="err">`</span>
<span class="k">rpc_decl </span><span class="o">=</span> <span class="err">`</span><span class="k">rpc_service</span><span class="err">`</span> <span class="k">ident </span><span class="err">`</span><span class="p">{</span><span class="err">`</span> <span class="k">rpc_method</span><span class="err">+</span> <span class="err">`</span><span class="p">}</span><span class="err">`</span>
<span class="k">rpc_method </span><span class="err">=</span> <span class="k">ident </span><span class="err">`</span><span class="p">(</span><span class="err">`</span> <span class="k">ident </span><span class="err">`</span><span class="p">)</span><span class="err">`</span> <span class="err">`:`</span> <span class="k">ident metadata </span><span class="err">`</span><span class="p">;</span><span class="err">`</span>
<span class="k">type </span><span class="o">=</span> <span class="err">`</span><span class="k">bool</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">byte</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">ubyte</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">short</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">ushort</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">int</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">uint</span><span class="err">`</span> <span class="p">|</span>
<span class="err">`</span><span class="k">float</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">long</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">ulong</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">double</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">int8</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">uint8</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">int16</span><span class="err">`</span> <span class="p">|</span>
<span class="err">`</span><span class="k">uint16</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">int32</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">uint32</span><span class="err">`</span><span class="p">|</span> <span class="err">`</span><span class="k">int64</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">uint64</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">float32</span><span class="err">`</span> <span class="p">|</span>
<span class="err">`</span><span class="k">float64</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">string</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="p">[</span><span class="err">`</span> <span class="k">type </span><span class="err">`</span><span class="p">]</span><span class="err">`</span> <span class="p">|</span> <span class="k">ident</span>
<span class="k">enumval_decl </span><span class="err">=</span> <span class="k">ident </span><span class="p">[</span> <span class="err">`=`</span> <span class="k">integer_constant </span><span class="p">]</span> <span class="k">metadata</span>
<span class="k">metadata </span><span class="err">=</span> <span class="p">[</span> <span class="err">`</span><span class="p">(</span><span class="err">`</span> <span class="k">commasep</span><span class="p">(</span> <span class="k">ident </span><span class="p">[</span> <span class="err">`:`</span> <span class="k">single_value </span><span class="p">]</span> <span class="p">)</span> <span class="err">`</span><span class="p">)</span><span class="err">`</span> <span class="p">]</span>
<span class="k">scalar </span><span class="err">=</span> <span class="k">boolean_constant </span><span class="p">|</span> <span class="k">integer_constant </span><span class="p">|</span> <span class="k">float_constant</span>
<span class="k">object </span><span class="err">=</span> <span class="err">`</span><span class="p">{</span><span class="err">`</span> <span class="k">commasep</span><span class="p">(</span> <span class="k">ident </span><span class="err">`:`</span> <span class="k">value </span><span class="p">)</span> <span class="err">`</span><span class="p">}</span><span class="err">`</span>
<span class="k">single_value </span><span class="err">=</span> <span class="k">scalar </span><span class="p">|</span> <span class="k">string_constant</span>
<span class="k">value </span><span class="err">=</span> <span class="k">single_value </span><span class="p">|</span> <span class="k">object </span><span class="p">|</span> <span class="err">`</span><span class="p">[</span><span class="err">`</span> <span class="k">commasep</span><span class="p">(</span> <span class="k">value </span><span class="p">)</span> <span class="err">`</span><span class="p">]</span><span class="err">`</span>
<span class="k">commasep</span><span class="p">(</span><span class="k">x</span><span class="p">)</span> <span class="err">=</span> <span class="p">[</span> <span class="k">x </span><span class="p">(</span> <span class="err">`</span><span class="p">,</span><span class="err">`</span> <span class="k">x </span><span class="p">)</span><span class="err">\*</span> <span class="p">]</span>
<span class="k">file_extension_decl </span><span class="err">=</span> <span class="err">`</span><span class="k">file_extension</span><span class="err">`</span> <span class="k">string_constant </span><span class="err">`</span><span class="p">;</span><span class="err">`</span>
<span class="k">file_identifier_decl </span><span class="o">=</span> <span class="err">`</span><span class="k">file_identifier</span><span class="err">`</span> <span class="k">string_constant </span><span class="err">`</span><span class="p">;</span><span class="err">`</span>
<span class="k">string_constant </span><span class="o">=</span> <span class="err">`\</span><span class="s2">&quot;.*?\&quot;</span><span class="err">`</span>
<span class="k">ident </span><span class="err">=</span> <span class="err">`</span><span class="p">[</span><span class="k">a-zA-Z_</span><span class="p">][</span><span class="k">a-zA-Z0-9_</span><span class="p">]</span><span class="err">*`</span>
<span class="err">`</span><span class="p">[</span><span class="err">:</span><span class="k">digit</span><span class="err">:</span><span class="p">]</span><span class="err">`</span> <span class="err">=</span> <span class="err">`</span><span class="p">[</span><span class="err">0</span><span class="o">-</span><span class="err">9</span><span class="p">]</span><span class="err">`</span>
<span class="err">`</span><span class="p">[</span><span class="err">:</span><span class="k">xdigit</span><span class="err">:</span><span class="p">]</span><span class="err">`</span> <span class="err">=</span> <span class="err">`</span><span class="p">[</span><span class="err">0</span><span class="o">-</span><span class="err">9</span><span class="k">a-fA-F</span><span class="p">]</span><span class="err">`</span>
<span class="k">dec_integer_constant </span><span class="err">=</span> <span class="err">`</span><span class="p">[</span><span class="o">-</span><span class="err">+</span><span class="p">]</span><span class="ni">?[:digit:]+`</span>
<span class="ni">hex_integer_constant = `[-+]?</span><span class="err">0</span><span class="p">[</span><span class="k">xX</span><span class="p">][</span><span class="err">:</span><span class="k">xdigit</span><span class="err">:</span><span class="p">]</span><span class="err">+`</span>
<span class="k">integer_constant </span><span class="err">=</span> <span class="k">dec_integer_constant </span><span class="p">|</span> <span class="k">hex_integer_constant</span>
<span class="k">dec_float_constant </span><span class="err">=</span> <span class="err">`</span><span class="p">[</span><span class="o">-</span><span class="err">+</span><span class="p">]</span><span class="ni">?(([.][:digit:]+)|([:digit:]+[.][:digit:]*)|([:digit:]+))([eE][-+]?</span><span class="p">[</span><span class="err">:</span><span class="k">digit</span><span class="err">:</span><span class="p">]</span><span class="err">+</span><span class="p">)</span><span class="ni">?`</span>
<span class="ni">hex_float_constant = `[-+]?</span><span class="err">0</span><span class="p">[</span><span class="k">xX</span><span class="p">](([.</span><span class="err">][:</span><span class="k">xdigit</span><span class="err">:]+)|([:</span><span class="k">xdigit</span><span class="err">:]+[.][:</span><span class="k">xdigit</span><span class="err">:]*)|([:</span><span class="k">xdigit</span><span class="err">:]+))([</span><span class="k">pP</span><span class="err">][-+]?[:</span><span class="k">digit</span><span class="err">:]+)`</span>
<span class="k">special_float_constant </span><span class="o">=</span> <span class="err">`</span><span class="p">[</span><span class="o">-</span><span class="err">+</span><span class="p">]</span><span class="err">?</span><span class="p">(</span><span class="k">nan</span><span class="p">|</span><span class="k">inf</span><span class="p">|</span><span class="k">infinity</span><span class="p">)</span><span class="err">`</span>
<span class="k">float_constant </span><span class="err">=</span> <span class="k">dec_float_constant </span><span class="p">|</span> <span class="k">hex_float_constant </span><span class="p">|</span> <span class="k">special_float_constant</span>
<span class="k">boolean_constant </span><span class="err">=</span> <span class="err">`</span><span class="k">true</span><span class="err">`</span> <span class="p">|</span> <span class="err">`</span><span class="k">false</span><span class="err">`</span>
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