<pre class="ebnf">
Expression = UnaryExpr | Expression binary_op Expression .
UnaryExpr  = PrimaryExpr | unary_op UnaryExpr .

binary_op  = "||" | "&amp;&amp;" | rel_op | add_op | mul_op .
rel_op     = "==" | "!=" | "&lt;" | "&lt;=" | ">" | ">=" .
add_op     = "+" | "-" | "|" | "^" .
mul_op     = "*" | "/" | "%" | "&lt;&lt;" | "&gt;&gt;" | "&amp;" | "&amp;^" .

unary_op   = "+" | "-" | "!" | "^" | "*" | "&amp;" | "&lt;-" .

TF_Buffer* TF_GetAllOpList() {
  std::vector<tensorflow::OpDef> op_defs;
  tensorflow::OpRegistry::Global()->GetRegisteredOps(&op_defs);
  tensorflow::OpList op_list;
  for (const auto& op : op_defs) {
    *(op_list.add_op()) = op;
  }
  TF_Buffer* ret = TF_NewBuffer();
  TF_CHECK_OK(MessageToBuffer(op_list, ret));
  return ret;
}

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