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) 2002-2020, 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).
34
35with Styleg;
36with Types; use Types;
37
38package Errutil is
39
40   ---------------------------------------------------------
41   -- Error Message Text and Message Insertion Characters --
42   ---------------------------------------------------------
43
44   --  Error message text strings are composed of lower case letters, digits
45   --  and the special characters space, comma, period, colon and semicolon,
46   --  apostrophe and parentheses. Special insertion characters can also
47   --  appear which cause the error message circuit to modify the given
48   --  string. For a full list of these, see the spec of errout.
49
50   -----------------------------------------------------
51   -- Format of Messages and Manual Quotation Control --
52   -----------------------------------------------------
53
54   --  Messages are generally all in lower case, except for inserted names
55   --  and appear in one of the following two forms:
56
57   --    error: text
58   --    warning: text
59
60   --  The prefixes error and warning are supplied automatically (depending
61   --  on the use of the ? insertion character), and the call to the error
62   --  message routine supplies the text. The "error: " prefix is omitted
63   --  in brief error message formats.
64
65   --  Reserved keywords in the message are in the default keyword case
66   --  (determined from the given source program), surrounded by quotation
67   --  marks. This is achieved by spelling the reserved word in upper case
68   --  letters, which is recognized as a request for insertion of quotation
69   --  marks by the error text processor. Thus for example:
70
71   --    Error_Msg_AP ("IS expected");
72
73   --  would result in the output of one of the following:
74
75   --    error: "is" expected
76   --    error: "IS" expected
77   --    error: "Is" expected
78
79   --  the choice between these being made by looking at the casing convention
80   --  used for keywords (actually the first compilation unit keyword) in the
81   --  source file.
82
83   --  In the case of names, the default mode for the error text processor
84   --  is to surround the name by quotation marks automatically. The case
85   --  used for the identifier names is taken from the source program where
86   --  possible, and otherwise is the default casing convention taken from
87   --  the source file usage.
88
89   --  In some cases, better control over the placement of quote marks is
90   --  required. This is achieved using manual quotation mode. In this mode,
91   --  one or more insertion sequences is surrounded by backquote characters.
92   --  The backquote characters are output as double quote marks, and normal
93   --  automatic insertion of quotes is suppressed between the double quotes.
94   --  For example:
95
96   --    Error_Msg_AP ("`END &;` expected");
97
98   --  generates a message like
99
100   --    error: "end Open_Scope;" expected
101
102   --  where the node specifying the name Open_Scope has been stored in
103   --  Error_Msg_Node_1 prior to the call. The great majority of error
104   --  messages operates in normal quotation mode.
105
106   --  Note: the normal automatic insertion of spaces before insertion
107   --  sequences (such as those that come from & and %) is suppressed in
108   --  manual quotation mode, so blanks, if needed as in the above example,
109   --  must be explicitly present.
110
111   ------------------------------
112   -- Error Output Subprograms --
113   ------------------------------
114
115   procedure Initialize;
116   --  Initializes for output of error messages. Must be called for each
117   --  file before using any of the other routines in the package.
118
119   procedure Finalize (Source_Type : String := "project");
120   --  Finalize processing of error messages for one file and output message
121   --  indicating the number of detected errors.
122   --  Source_Type is used in verbose mode to indicate the type of the source
123   --  being parsed (project file, definition file or input file for the
124   --  preprocessor).
125
126   procedure Error_Msg (Msg : String; Flag_Location : Source_Ptr);
127   --  Output a message at specified location
128
129   procedure Error_Msg_S (Msg : String);
130   --  Output a message at current scan pointer location
131
132   procedure Error_Msg_SC (Msg : String);
133   --  Output a message at the start of the current token, unless we are at
134   --  the end of file, in which case we always output the message after the
135   --  last real token in the file.
136
137   procedure Error_Msg_SP (Msg : String);
138   --  Output a message at the start of the previous token
139
140   procedure Set_Ignore_Errors (To : Boolean);
141   --  Indicate, when To = True, that all reported errors should
142   --  be ignored. By default reported errors are not ignored.
143
144   package Style is new Styleg
145     (Error_Msg    => Error_Msg,
146      Error_Msg_S  => Error_Msg_S,
147      Error_Msg_SC => Error_Msg_SC,
148      Error_Msg_SP => Error_Msg_SP);
149   --  Instantiation of the generic style package, suitable for an
150   --  instantiation of Scng.
151
152end Errutil;
153