------------------------------------------------------------------------------
-- --
-- ASIS Tester And iNTerpreter (ASIStant) COMPONENTS --
-- --
-- A S I S T A N T . L _ P A R S E R --
-- --
-- S p e c --
-- --
-- Copyright (C) 1997-2013, Free Software Foundation, Inc. --
-- --
-- ASIStant is free software; you can redistribute it and/or modify it --
-- under terms of the GNU General Public License as published by the Free --
-- Software Foundation; either version 2, or (at your option) any later --
-- version. ASIStant is distributed in the hope that it will be useful, --
-- but WITHOUT ANY WARRANTY; without even the implied warranty of MER- --
-- CHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General --
-- Public License for more details. You should have received a copy of the --
-- GNU General Public License distributed with GNAT; see file COPYING. If --
-- not, write to the Free Software Foundation, 59 Temple Place Suite 330, --
-- Boston, MA 02111-1307, USA. --
-- --
-- ASIStant is an evolution of ASIStint tool that was created by --
-- Vasiliy Fofanov as part of a collaboration between Software Engineering --
-- Laboratory of the Swiss Federal Institute of Technology in Lausanne, --
-- Switzerland, and the Scientific Research Computer Center of the Moscow --
-- University, Russia, supported by the Swiss National Science Foundation --
-- grant #7SUPJ048247, "Development of ASIS for GNAT with industry quality" --
-- --
-- ASIStant is distributed as a part of the ASIS implementation for GNAT --
-- (ASIS-for-GNAT) and is maintained by AdaCore (http://www.adacore.com). --
-- --
------------------------------------------------------------------------------
with Ada.Characters.Handling; use Ada.Characters.Handling;
with Ada.Strings.Wide_Maps; use Ada.Strings.Wide_Maps;
with ASIStant.FuncEnum; use ASIStant.FuncEnum;
package ASIStant.L_Parser is
------------------------------------------------------------------------------
-- This package provides token parsing for the ASIStant language
------------------------------------------------------------------------------
CS_White_Spaces : Wide_Character_Set :=
To_Set (To_Wide_String (ASCII.NUL & ASCII.HT & ' '));
CS_Special_Tokens : Wide_Character_Set :=
To_Set ("""-+*/;,()");
CS_Token_Separators : Wide_Character_Set :=
CS_White_Spaces or CS_Special_Tokens;
-- Sets of symbols that require special processing and/or separate tokens
type Token_Stream is
record
Text : String_Ptr;
Cur_Token_Start : Natural := 0;
Cur_Token_End : Natural := 0;
Prev_Token_Start : Natural := 0;
Prev_Token_End : Natural := 0;
end record;
-- this structure is used for token parsing. Text accesses the string
-- being parsed, other fields are necessary to keep track of the current
-- and previous tokens. Initial value (Cur_Token_Start,Cur_Token_End)
-- of an active token stream should be (1,0)
CurTokStream : Token_Stream := (null, 0, 0, 0, 0);
procedure Next_Token (TS : in out Token_Stream);
-- advances to the next token in stream
procedure Prev_Token (TS : in out Token_Stream);
-- undoes the last Next_Token call, but may retreat only one token back
function Cur_Token (TS : Token_Stream) return Wide_String;
-- returns current token in stream
function Is_ID (TS : Token_Stream) return Boolean;
-- returns True if the current token is correct ID, False otherwise;
-- the correct ID is a combination of letters, digits and underline
-- characters starting with a letter
function Is_Active (TS : Token_Stream) return Boolean;
-- returns True if the token stream still has tokens, False otherwise
function Next_Line (S : Wide_String) return Natural;
-- Skips to next line in token stream
end ASIStant.L_Parser;