1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                              E R R U T I L                               --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--          Copyright (C) 2002-2012, Free Software Foundation, Inc.         --
10--                                                                          --
11-- GNAT is free software;  you can  redistribute it  and/or modify it under --
12-- terms of the  GNU General Public License as published  by the Free Soft- --
13-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
14-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
15-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
16-- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
17-- for  more details.  You should have  received  a copy of the GNU General --
18-- Public License  distributed with GNAT; see file COPYING3.  If not, go to --
19-- http://www.gnu.org/licenses for a complete copy of the license.          --
20--                                                                          --
21-- GNAT was originally developed  by the GNAT team at  New York University. --
22-- Extensive contributions were provided by Ada Core Technologies Inc.      --
23--                                                                          --
24------------------------------------------------------------------------------
25
26--  This package contains routines to output error messages and the
27--  corresponding instantiation of Styleg, suitable to instantiate Scng.
28
29--  It uses the same global variables as Errout, located in packages Atree and
30--  Err_Vars. Like Errout, it also uses the common variables and routines
31--  in package Erroutc.
32
33--  This package is used by the preprocessor (gprep.adb) and the project
34--  manager (prj-err.ads).
35
36with Styleg;
37with Types; use Types;
38
39package Errutil is
40
41   ---------------------------------------------------------
42   -- Error Message Text and Message Insertion Characters --
43   ---------------------------------------------------------
44
45   --  Error message text strings are composed of lower case letters, digits
46   --  and the special characters space, comma, period, colon and semicolon,
47   --  apostrophe and parentheses. Special insertion characters can also
48   --  appear which cause the error message circuit to modify the given
49   --  string. For a full list of these, see the spec of errout.
50
51   -----------------------------------------------------
52   -- Format of Messages and Manual Quotation Control --
53   -----------------------------------------------------
54
55   --  Messages are generally all in lower case, except for inserted names
56   --  and appear in one of the following two forms:
57
58   --    error: text
59   --    warning: text
60
61   --  The prefixes error and warning are supplied automatically (depending
62   --  on the use of the ? insertion character), and the call to the error
63   --  message routine supplies the text. The "error: " prefix is omitted
64   --  in brief error message formats.
65
66   --  Reserved keywords in the message are in the default keyword case
67   --  (determined from the given source program), surrounded by quotation
68   --  marks. This is achieved by spelling the reserved word in upper case
69   --  letters, which is recognized as a request for insertion of quotation
70   --  marks by the error text processor. Thus for example:
71
72   --    Error_Msg_AP ("IS expected");
73
74   --  would result in the output of one of the following:
75
76   --    error: "is" expected
77   --    error: "IS" expected
78   --    error: "Is" expected
79
80   --  the choice between these being made by looking at the casing convention
81   --  used for keywords (actually the first compilation unit keyword) in the
82   --  source file.
83
84   --  In the case of names, the default mode for the error text processor
85   --  is to surround the name by quotation marks automatically. The case
86   --  used for the identifier names is taken from the source program where
87   --  possible, and otherwise is the default casing convention taken from
88   --  the source file usage.
89
90   --  In some cases, better control over the placement of quote marks is
91   --  required. This is achieved using manual quotation mode. In this mode,
92   --  one or more insertion sequences is surrounded by backquote characters.
93   --  The backquote characters are output as double quote marks, and normal
94   --  automatic insertion of quotes is suppressed between the double quotes.
95   --  For example:
96
97   --    Error_Msg_AP ("`END &;` expected");
98
99   --  generates a message like
100
101   --    error: "end Open_Scope;" expected
102
103   --  where the node specifying the name Open_Scope has been stored in
104   --  Error_Msg_Node_1 prior to the call. The great majority of error
105   --  messages operates in normal quotation mode.
106
107   --  Note: the normal automatic insertion of spaces before insertion
108   --  sequences (such as those that come from & and %) is suppressed in
109   --  manual quotation mode, so blanks, if needed as in the above example,
110   --  must be explicitly present.
111
112   ------------------------------
113   -- Error Output Subprograms --
114   ------------------------------
115
116   procedure Initialize;
117   --  Initializes for output of error messages. Must be called for each
118   --  file before using any of the other routines in the package.
119
120   procedure Finalize (Source_Type : String := "project");
121   --  Finalize processing of error messages for one file and output message
122   --  indicating the number of detected errors.
123   --  Source_Type is used in verbose mode to indicate the type of the source
124   --  being parsed (project file, definition file or input file for the
125   --  preprocessor).
126
127   procedure Error_Msg (Msg : String; Flag_Location : Source_Ptr);
128   --  Output a message at specified location
129
130   procedure Error_Msg_S (Msg : String);
131   --  Output a message at current scan pointer location
132
133   procedure Error_Msg_SC (Msg : String);
134   --  Output a message at the start of the current token, unless we are at
135   --  the end of file, in which case we always output the message after the
136   --  last real token in the file.
137
138   procedure Error_Msg_SP (Msg : String);
139   --  Output a message at the start of the previous token
140
141   procedure Set_Ignore_Errors (To : Boolean);
142   --  Indicate, when To = True, that all reported errors should
143   --  be ignored. By default reported errors are not ignored.
144
145   package Style is new Styleg
146     (Error_Msg    => Error_Msg,
147      Error_Msg_S  => Error_Msg_S,
148      Error_Msg_SC => Error_Msg_SC,
149      Error_Msg_SP => Error_Msg_SP);
150   --  Instantiation of the generic style package, suitable for an
151   --  instantiation of Scng.
152
153end Errutil;
154