ada.2/err.ads

   1 with Ada.Exceptions;
   2 with Ada.Strings.Unbounded;
   3
   4 with Types;
   5 --  We declare a variable of type Types.T.
   6 pragma Elaborate (Types);
   7
   8 package Err is
   9
  10    --  Error handling.
  11
  12    --  Built-in function.
  13    function Throw (Args : in Types.T_Array) return Types.T;
  14
  15    --  Ada exceptions can only carry an immutable String in each
  16    --  occurence, so we require a global variable to store the last
  17    --  exception as a Mal object anyway, and may as well use it for
  18    --  simple string messages.
  19
  20    Error : exception;
  21    Data  : Types.T;
  22    Trace : Ada.Strings.Unbounded.Unbounded_String;
  23
  24    --  Convenient shortcuts.
  25
  26    procedure Raise_With (Message : in String) with No_Return;
  27    --  Similar to a "raise with Message" Ada statement.
  28    --  Store the message into Data,
  29    --  store the message and "Uncaught exception: " into Trace,
  30    --  then raise Error.
  31
  32    procedure Raise_In_Mal (E : in Ada.Exceptions.Exception_Occurrence)
  33      with No_Return;
  34    --  Raise_With (Ada.Exceptions.Exception_Information (E))
  35
  36    procedure Add_Trace_Line (Action : in String;
  37                              Ast    : in Types.T);
  38    --  Appends a line like "Action: Ast" to Trace.
  39
  40    procedure Check (Condition : in Boolean;
  41                     Message   : in String) with Inline;
  42    --  Raise_With if Condition fails.
  43
  44    --  It is probably more efficient to construct a boolean and call
  45    --  this procedure once, as "inline" is only a recommendation.
  46
  47    --  Beware of the classical performance issue that the Message is
  48    --  formatted even if the Condition does not hold.
  49
  50 end Err;