anchor.diff:  
   
   %% =====================================================================
  -%% @spec match_expr(Pattern::syntaxTree(), Body::syntaxTree()) ->
  -%%           syntaxTree()
  -%%
   %% @doc Creates an abstract match-expression. The result represents
   %% "<code><em>Pattern</em> = <em>Body</em></code>".
   %%
  
positive.code: 
  
  %% =====================================================================
  %% @spec float(Value::float()) -> syntaxTree()
  %%
  %% @doc Creates an abstract floating-point literal. The lexical
  %% representation is the decimal floating-point numeral of
  %% <code>Value</code>.
  
negative.code: %% @see data/1
  %% @see type/1
  
  -spec tree(atom(), term()) -> #tree{}.
  
  tree(Type, Data) ->
      #tree{type = Type, data = Data}.
  
  
  %% =====================================================================
  %% @doc <em>For special purposes only</em>. Returns <code>true</code> if
  %% <code>Tree</code> is an abstract syntax tree and <code>false</code>
  %% otherwise.
  