val build_tuple_nodup_code :
  Code_selection_context.code_selection_context ->
  Xquery_common_ast.crname ->
  Execution_context.algebra_context ->
  Physical_value.tuple_unit Cursor.cursor ->
  Physical_value.tuple_unit Cursor.cursor
val build_distinct_code :
  Code_selection_context.code_selection_context ->
  Algebra_type.algop_expr ->
  Xquery_common_ast.crname ->
  Algebra_type.alg_eval_code_dep *
  Code_selection_context.code_selection_context
val build_default_tuple_tree_pattern_code :
  Code_selection_context.code_selection_context ->
  Xquery_common_ast.crname ->
  Xquery_algebra_ast.twig_pattern ->
  unit ->
  Algebra_type.eval_fun ->
  Execution_context.algebra_context ->
  Physical_value.tuple_unit Cursor.cursor ->
  Physical_value.tuple_unit Cursor.cursor
val effective_boolean_value :
  Physical_value.item Cursor.cursor -> Datatypes.xs_boolean
val get_treejoin_attrs :
  Xquery_algebra_ast.twig_pattern ->
  Xquery_common_ast.axis * int ->
  Namespace_names.rqname * Xquery_common_ast.axis *
  Xquery_algebra_ast.anode_test