gcc/ada/stylesw.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                              S T Y L E S W                               --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2005, 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 2,  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 COPYING.  If not, write --
  19 -- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, USA.                                              --
  21 --                                                                          --
  22 -- GNAT was originally developed  by the GNAT team at  New York University. --
  23 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  24 --                                                                          --
  25 ------------------------------------------------------------------------------
  26
  27 --  This package contains the style switches used for setting style options.
  28 --  The only clients of this package are the body of Style and the body of
  29 --  Switches. All other style checking issues are handled using the public
  30 --  interfaces in the spec of Style.
  31
  32 with Types; use Types;
  33
  34 package Stylesw is
  35
  36    --------------------------
  37    -- Style Check Switches --
  38    --------------------------
  39
  40    --  These flags are used to control the details of the style checking
  41    --  options. The default values shown here correspond to no style
  42    --  checking. If any of these values is set to a non-default value,
  43    --  then Opt.Style_Check is set True to active calls to this package.
  44
  45    --  The actual mechanism for setting these switches to other than
  46    --  default values is via the Set_Style_Check_Option procedure or
  47    --  through a call to Set_Default_Style_Check_Options. They should
  48    --  not be set directly in any other manner.
  49
  50    Style_Check_Attribute_Casing : Boolean := False;
  51    --  This can be set True by using the -gnatg or -gnatya switches. If
  52    --  it is True, then attribute names (including keywords such as
  53    --  digits used as attribute names) must be in mixed case.
  54
  55    Style_Check_Blanks_At_End : Boolean := False;
  56    --  This can be set True by using the -gnatg or -gnatyb switches. If
  57    --  it is True, then spaces at the end of lines are not permitted.
  58
  59    Style_Check_Blank_Lines : Boolean := False;
  60    --  This can be set True by using the -gnatg or -gnatyu switches. If
  61    --  it is True, then multiple blank lines are not permitted, and there
  62    --  may not be a blank line at the end of the file.
  63
  64    Style_Check_Comments : Boolean := False;
  65    --  This can be set True by using the -gnatg or -gnatyc switches. If
  66    --  it is True, then comments are style checked as follows:
  67    --
  68    --    All comments must be at the start of the line, or the first
  69    --    minus must be preceded by at least one space.
  70    --
  71    --    For a comment that is not at the start of a line, the only
  72    --    requirement is that a space follow the comment characters.
  73    --
  74    --    For a coment that is at the start of the line, one of the
  75    --    following conditions must hold:
  76    --
  77    --      The comment characters are the only non-blank characters on the line
  78    --
  79    --      The comment characters are followed by an exclamation point (the
  80    --      sequence --! is used by gnatprep for marking deleted lines).
  81    --
  82    --      The comment characters are followed by two space characters
  83    --
  84    --      The line consists entirely of minus signs
  85    --
  86    --      The comment characters are followed by a single space, and the
  87    --      last two characters on the line are also comment characters.
  88    --
  89    --  Note: the reason for the last two conditions is to allow "boxed"
  90    --  comments where only a single space separates the comment characters.
  91
  92    Style_Check_DOS_Line_Terminator : Boolean := False;
  93    --  This can be set true by using the -gnatg or -gnatyd switches. If
  94    --  it is True, then the line terminator must be a single LF, without an
  95    --  associated CR (e.g. DOS line terminator sequence CR/LF not allowed).
  96
  97    Style_Check_End_Labels : Boolean := False;
  98    --  This can be set True by using the -gnatg or -gnatye switches. If
  99    --  it is True, then optional END labels must always be present.
 100
 101    Style_Check_Form_Feeds : Boolean := False;
 102    --  This can be set True by using the -gnatg or -gnatyf switches. If
 103    --  it is True, then form feeds and vertical tabs are not allowed in
 104    --  the source text.
 105
 106    Style_Check_Horizontal_Tabs : Boolean := False;
 107    --  This can be set True by using the -gnatg or -gnatyh switches. If
 108    --  it is True, then horizontal tabs are not allowed in source text.
 109
 110    Style_Check_If_Then_Layout : Boolean := False;
 111    --  This can be set True by using the -gnatg or -gnatyi switches. If
 112    --  it is True, then a THEN keyword may not appear on the line that
 113    --  immediately follows the line containing the corresponding IF.
 114    --
 115    --  This permits one of two styles for IF-THEN layout. Either the
 116    --  IF and THEN keywords are on the same line, where the condition
 117    --  is short enough, or the conditions are continued over to the
 118    --  lines following the IF and the THEN stands on its own. For
 119    --  example:
 120    --
 121    --    if X > Y then
 122    --
 123    --    if X > Y
 124    --      and then Y < Z
 125    --    then
 126    --
 127    --  are allowed, but
 128    --
 129    --    if X > Y
 130    --    then
 131    --
 132    --  is not allowed.
 133
 134    Style_Check_Indentation : Column_Number range 0 .. 9 := 0;
 135    --  This can be set non-zero by using the -gnatg or -gnatyn (n a digit)
 136    --  switches. If it is non-zero it activates indentation checking with
 137    --  the indicated indentation value. A value of zero turns off checking.
 138    --  The requirement is that any new statement, line comment, declaration
 139    --  or keyword such as END, start on a column that is a multiple of the
 140    --  indentiation value.
 141
 142    Style_Check_Keyword_Casing : Boolean := False;
 143    --  This can be set True by using the -gnatg or -gnatyk switches. If
 144    --  it is True, then keywords are required to be in all lower case.
 145    --  This rule does not apply to keywords such as digits appearing as
 146    --  an attribute name.
 147
 148    Style_Check_Max_Line_Length : Boolean := False;
 149    --  This can be set True by using the -gnatg or -gnatym/M switches.
 150    --  If it is True, it activates checking for a maximum line length of
 151    --  Style_Max_Line_Length characters.
 152
 153    Style_Check_Max_Nesting_Level : Boolean := False;
 154    --  This can be set True by using -gnatyLnnn with a value other than
 155    --  zero (a value of zero resets it to False). If True, it activates
 156    --  checking the maximum nesting level against Style_Max_Nesting_Level.
 157
 158    Style_Check_Order_Subprograms : Boolean := False;
 159    --  This can be set True by using the -gnatg or -gnatyo switch. If it
 160    --  is True, then names of subprogram bodies must be in alphabetical
 161    --  order (not taking casing into account).
 162
 163    Style_Check_Pragma_Casing : Boolean := False;
 164    --  This can be set True by using the -gnatg or -gnatyp switches. If
 165    --  it is True, then pragma names must use mixed case.
 166
 167    Style_Check_Layout : Boolean := False;
 168    --  This can be set True by using the -gnatg or -gnatyl switches. If
 169    --  it is True, it activates checks that constructs are indented as
 170    --  suggested by the examples in the RM syntax, e.g. that the ELSE
 171    --  keyword must line up with the IF keyword.
 172
 173    Style_Check_References : Boolean := False;
 174    --  This can be set True by using the -gnatg or -gnatyr switches. If
 175    --  it is True, then all references to declared identifiers are
 176    --  checked. The requirement is that casing of the reference be the
 177    --  same as the casing of the corresponding declaration.
 178
 179    Style_Check_Specs : Boolean := False;
 180    --  This can be set True by using the -gnatg or -gnatys switches. If
 181    --  it is True, then separate specs are required to be present for
 182    --  all procedures except parameterless library level procedures.
 183    --  The exception means that typical main programs do not require
 184    --  separate specs.
 185
 186    Style_Check_Standard : Boolean := False;
 187    --  This can be set True by using the -gnatg or -gnatyn switches. If
 188    --  it is True, then any references to names in Standard have to be
 189    --  in mixed case mode (e.g. Integer, Boolean).
 190
 191    Style_Check_Tokens : Boolean := False;
 192    --  This can be set True by using the -gnatg or -gnatyt switches. If
 193    --  it is True, then the style check that requires canonical spacing
 194    --  between various punctuation tokens as follows:
 195    --
 196    --    ABS and NOT must be followed by a space
 197    --
 198    --    => must be surrounded by spaces
 199    --
 200    --    <> must be preceded by a space or left paren
 201    --
 202    --    Binary operators other than ** must be surrounded by spaces.
 203    --    There is no restriction on the layout of the ** binary operator.
 204    --
 205    --    Colon must be surrounded by spaces
 206    --
 207    --    Colon-equal (assignment) must be surrounded by spaces
 208    --
 209    --    Comma must be the first non-blank character on the line, or be
 210    --    immediately preceded by a non-blank character, and must be followed
 211    --    by a blank.
 212    --
 213    --    A space must precede a left paren following a digit or letter,
 214    --    and a right paren must not be followed by a space (it can be
 215    --    at the end of the line).
 216    --
 217    --    A right paren must either be the first non-blank character on
 218    --    a line, or it must be preceded by a non-blank character.
 219    --
 220    --    A semicolon must not be preceded by a blank, and must not be
 221    --    followed by a non-blank character.
 222    --
 223    --    A unary plus or minus may not be followed by a space
 224    --
 225    --    A vertical bar must be surrounded by spaces
 226    --
 227    --  Note that a requirement that a token be preceded by a space is
 228    --  met by placing the token at the start of the line, and similarly
 229    --  a requirement that a token be followed by a space is met by
 230    --  placing the token at the end of the line. Note that in the case
 231    --  where horizontal tabs are permitted, a horizontal tab is acceptable
 232    --  for meeting the requirement for a space.
 233
 234    Style_Check_Xtra_Parens : Boolean := False;
 235    --  This can be set True by using the -gnatg or -gnatyx switch. If true,
 236    --  then it is not allowed to enclose entire conditional expressions
 237    --  in parentheses (C style).
 238
 239    Style_Max_Line_Length : Int := 0;
 240    --  Value used to check maximum line length. Gets reset as a result of
 241    --  use of -gnatym or -gnatyMnnn switches (or by use of -gnatg). This
 242    --  value is only read if Style_Check_Max_Line_Length is True.
 243
 244    Style_Max_Nesting_Level : Int := 0;
 245    --  Value used to check maximum nesting level. Gets reset as a result
 246    --  of use of the -gnatyLnnn switch. This value is only read if
 247    --  Style_Check_Max_Nesting_Level is True.
 248
 249    -----------------
 250    -- Subprograms --
 251    -----------------
 252
 253    procedure Set_Default_Style_Check_Options;
 254    --  This procedure is called to set the default style checking options
 255    --  in response to a -gnaty switch with no suboptions.
 256
 257    Style_Msg_Buf : String (1 .. 80);
 258    Style_Msg_Len : Natural;
 259    --  Used to return
 260
 261    procedure Set_Style_Check_Options
 262      (Options  : String;
 263       OK       : out Boolean;
 264       Err_Col  : out Natural);
 265    --  This procedure is called to set the style check options that correspond
 266    --  to the characters in the given Options string. If all options are valid,
 267    --  they are set in an additive manner: any previous options are retained
 268    --  unless overridden.
 269    --
 270    --  If all options given are valid, then OK is True, Err_Col is set to
 271    --  Options'Last + 1, and Style_Msg_Buf/Style_Msg_Len are unchanged.
 272    --
 273    --  If an invalid character is found, then OK is False on exit, and Err_Col
 274    --  is the index in options of the bad character. In this case Style_Msg_Len
 275    --  is set and Style_Msg_Buf (1 .. Style_Msg_Len) has a detailed message
 276    --  describing the error.
 277
 278    procedure Set_Style_Check_Options (Options : String);
 279    --  Like the above procedure, but used when the Options string is known to
 280    --  be valid. This is for example appopriate for calls where the string ==
 281    --  was obtained by Save_Style_Check_Options.
 282
 283    procedure Reset_Style_Check_Options;
 284    --  Sets all style check options to off
 285
 286    subtype Style_Check_Options is String (1 .. 64);
 287    --  Long enough string to hold all options from Save call below
 288
 289    procedure Save_Style_Check_Options (Options : out Style_Check_Options);
 290    --  Sets Options to represent current selection of options. This
 291    --  set can be restored by first calling Reset_Style_Check_Options,
 292    --  and then calling Set_Style_Check_Options with the Options string.
 293
 294 end Stylesw;