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) 1992-2008, 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 the style switches used for setting style options.
  27 --  The only clients of this package are the body of Style and the body of
  28 --  Switches. All other style checking issues are handled using the public
  29 --  interfaces in the spec of Style.
  30
  31 with Types; use Types;
  32
  33 package Stylesw is
  34
  35    --------------------------
  36    -- Style Check Switches --
  37    --------------------------
  38
  39    --  These flags are used to control the details of the style checking
  40    --  options. The default values shown here correspond to no style checking.
  41
  42    --  If any of these values is set to a non-default value, then
  43    --  Opt.Style_Check is set True to active calls to this package.
  44
  45    --  The actual mechanism for setting these switches to other than default
  46    --  values is via the Set_Style_Check_Option procedure or through a call to
  47    --  Set_Default_Style_Check_Options. They should not be set directly in any
  48    --  other manner.
  49
  50    Style_Check_Array_Attribute_Index : Boolean := False;
  51    --  This can be set True by using -gnatg or -gnatyA switches. If it is True
  52    --  then index numbers for array attributes (like Length) are required to
  53    --  be absent for one-dimensional arrays and present for multi-dimensional
  54    --  array attribute references.
  55
  56    Style_Check_Attribute_Casing : Boolean := False;
  57    --  This can be set True by using the -gnatg or -gnatya switches. If it is
  58    --  True, then attribute names (including keywords such as digits used as
  59    --  attribute names) must be in mixed case.
  60
  61    Style_Check_Blanks_At_End : Boolean := False;
  62    --  This can be set True by using the -gnatg or -gnatyb switches. If it is
  63    --  True, then spaces at the end of lines are not permitted.
  64
  65    Style_Check_Blank_Lines : Boolean := False;
  66    --  This can be set True by using the -gnatg or -gnatyu switches. If it is
  67    --  True, then multiple blank lines are not permitted, and there may not be
  68    --  a blank line at the end of the file.
  69
  70    Style_Check_Comments : Boolean := False;
  71    --  This can be set True by using the -gnatg or -gnatyc switches. If it is
  72    --  True, then comments are style checked as follows:
  73    --
  74    --    All comments must be at the start of the line, or the first minus must
  75    --    be preceded by at least one space.
  76    --
  77    --    For a comment that is not at the start of a line, the only requirement
  78    --    is that a space follow the comment characters.
  79    --
  80    --    For a comment that is at the start of the line, one of the following
  81    --    conditions must hold:
  82    --
  83    --      The comment characters are the only non-blank characters on the line
  84    --
  85    --      The comment characters are followed by an exclamation point (the
  86    --      sequence --! is used by gnatprep for marking deleted lines).
  87    --
  88    --      The comment characters are followed by two space characters
  89    --
  90    --      The line consists entirely of minus signs
  91    --
  92    --      The comment characters are followed by a single space, and the last
  93    --      two characters on the line are also comment characters.
  94    --
  95    --  Note: the reason for the last two conditions is to allow "boxed"
  96    --  comments where only a single space separates the comment characters.
  97
  98    Style_Check_DOS_Line_Terminator : Boolean := False;
  99    --  This can be set true by using the -gnatg or -gnatyd switches. If it
 100    --  is True, then the line terminator must be a single LF, without an
 101    --  associated CR (e.g. DOS line terminator sequence CR/LF not allowed).
 102
 103    Style_Check_End_Labels : Boolean := False;
 104    --  This can be set True by using the -gnatg or -gnatye switches. If it is
 105    --  True, then optional END labels must always be present.
 106
 107    Style_Check_Form_Feeds : Boolean := False;
 108    --  This can be set True by using the -gnatg or -gnatyf switches. If it is
 109    --  True, then form feeds and vertical tabs are not allowed in the source
 110    --  text.
 111
 112    Style_Check_Horizontal_Tabs : Boolean := False;
 113    --  This can be set True by using the -gnatg or -gnatyh switches. If it is
 114    --  True, then horizontal tabs are not allowed in source text.
 115
 116    Style_Check_If_Then_Layout : Boolean := False;
 117    --  This can be set True by using the -gnatg or -gnatyi switches. If it is
 118    --  True, then a THEN keyword may not appear on the line that immediately
 119    --  follows the line containing the corresponding IF.
 120    --
 121    --  This permits one of two styles for IF-THEN layout. Either the IF and
 122    --  THEN keywords are on the same line, where the condition is short enough,
 123    --  or the conditions are continued over to the lines following the IF and
 124    --  the THEN stands on its own. For example:
 125    --
 126    --    if X > Y then
 127    --
 128    --    if X > Y
 129    --      and then Y < Z
 130    --    then
 131    --
 132    --  are allowed, but
 133    --
 134    --    if X > Y
 135    --    then
 136    --
 137    --  is not allowed.
 138
 139    Style_Check_Indentation : Column_Number range 0 .. 9 := 0;
 140    --  This can be set non-zero by using the -gnatg or -gnatyn (n a digit)
 141    --  switches. If it is non-zero it activates indentation checking with the
 142    --  indicated indentation value. A value of zero turns off checking. The
 143    --  requirement is that any new statement, line comment, declaration or
 144    --  keyword such as END, start on a column that is a multiple of the
 145    --  indentation value.
 146
 147    Style_Check_Keyword_Casing : Boolean := False;
 148    --  This can be set True by using the -gnatg or -gnatyk switches. If it is
 149    --  True, then keywords are required to be in all lower case. This rule does
 150    --  not apply to keywords such as digits appearing as an attribute name.
 151
 152    Style_Check_Layout : Boolean := False;
 153    --  This can be set True by using the -gnatg or -gnatyl switches. If it is
 154    --  True, it activates checks that constructs are indented as suggested by
 155    --  the examples in the RM syntax, e.g. that the ELSE keyword must line up
 156    --  with the IF keyword.
 157
 158    Style_Check_Max_Line_Length : Boolean := False;
 159    --  This can be set True by using the -gnatg or -gnatym/M switches. If
 160    --  it is True, it activates checking for a maximum line length of
 161    --  Style_Max_Line_Length characters.
 162
 163    Style_Check_Max_Nesting_Level : Boolean := False;
 164    --  This can be set True by using -gnatyLnnn with a value other than zero
 165    --  (a value of zero resets it to False). If True, it activates checking
 166    --  the maximum nesting level against Style_Max_Nesting_Level.
 167
 168    Style_Check_Mode_In : Boolean := False;
 169    --  This can be set True by using -gnatyI. If True, it activates checking
 170    --  that mode IN is not used on its own (since it is the default).
 171
 172    Style_Check_Order_Subprograms : Boolean := False;
 173    --  This can be set True by using the -gnatg or -gnatyo switch. If it is
 174    --  True, then names of subprogram bodies must be in alphabetical order
 175    --  (not taking casing into account).
 176
 177    Style_Check_Pragma_Casing : Boolean := False;
 178    --  This can be set True by using the -gnatg or -gnatyp switches. If it is
 179    --  True, then pragma names must use mixed case.
 180
 181    Style_Check_References : Boolean := False;
 182    --  This can be set True by using the -gnatg or -gnatyr switches. If it is
 183    --  True, then all references to declared identifiers are checked. The
 184    --  requirement is that casing of the reference be the same as the casing
 185    --  of the corresponding declaration.
 186
 187    Style_Check_Separate_Stmt_Lines : Boolean := False;
 188    --  This can be set True by using the -gnatg or -gnatyS switches. If it is
 189    --  TRUE, then for the case of keywords THEN (not preceded by AND) or ELSE
 190    --  (not preceded by OR) which introduce a conditionally executed statement
 191    --  sequence, there must be no tokens on the same line as the keyword, so
 192    --  that coverage testing can clearly identify execution of the statement
 193    --  sequence. A comment is permitted, as is THEN ABORT or a PRAGMA keyword
 194    --  after ELSE (a common style to specify the condition for the ELSE).
 195
 196    Style_Check_Specs : Boolean := False;
 197    --  This can be set True by using the -gnatg or -gnatys switches. If it is
 198    --  True, then separate specs are required to be present for all procedures
 199    --  except parameterless library level procedures. The exception means that
 200    --  typical main programs do not require separate specs.
 201
 202    Style_Check_Standard : Boolean := False;
 203    --  This can be set True by using the -gnatg or -gnatyn switches. If it is
 204    --  True, then any references to names in Standard have to be in mixed case
 205    --  mode (e.g. Integer, Boolean).
 206
 207    Style_Check_Tokens : Boolean := False;
 208    --  This can be set True by using the -gnatg or -gnatyt switches. If it is
 209    --  True, then the style check that requires canonical spacing between
 210    --  various punctuation tokens as follows:
 211    --
 212    --    ABS and NOT must be followed by a space
 213    --
 214    --    => must be surrounded by spaces
 215    --
 216    --    <> must be preceded by a space or left paren
 217    --
 218    --    Binary operators other than ** must be surrounded by spaces.
 219    --
 220    --    There is no restriction on the layout of the ** binary operator.
 221    --
 222    --    Colon must be surrounded by spaces
 223    --
 224    --    Colon-equal (assignment) must be surrounded by spaces
 225    --
 226    --    Comma must be the first non-blank character on the line, or be
 227    --    immediately preceded by a non-blank character, and must be followed
 228    --    by a blank.
 229    --
 230    --    A space must precede a left paren following a digit or letter, and a
 231    --    right paren must not be followed by a space (it can be at the end of
 232    --    the line).
 233    --
 234    --    A right paren must either be the first non-blank character on a line,
 235    --    or it must be preceded by a non-blank character.
 236    --
 237    --    A semicolon must not be preceded by a blank, and must not be followed
 238    --    by a non-blank character.
 239    --
 240    --    A unary plus or minus may not be followed by a space
 241    --
 242    --    A vertical bar must be surrounded by spaces
 243    --
 244    --  Note that a requirement that a token be preceded by a space is met by
 245    --  placing the token at the start of the line, and similarly a requirement
 246    --  that a token be followed by a space is met by placing the token at
 247    --  the end of the line. Note that in the case where horizontal tabs are
 248    --  permitted, a horizontal tab is acceptable for meeting the requirement
 249    --  for a space.
 250
 251    Style_Check_Xtra_Parens : Boolean := False;
 252    --  This can be set True by using the -gnatg or -gnatyx switch. If true,
 253    --  then it is not allowed to enclose entire conditional expressions in
 254    --  parentheses (C style).
 255
 256    Style_Max_Line_Length : Int := 0;
 257    --  Value used to check maximum line length. Gets reset as a result of use
 258    --  of -gnatym or -gnatyMnnn switches (or by use of -gnatg). This value is
 259    --  only read if Style_Check_Max_Line_Length is True.
 260
 261    Style_Max_Nesting_Level : Int := 0;
 262    --  Value used to check maximum nesting level. Gets reset as a result
 263    --  of use of the -gnatyLnnn switch. This value is only read if
 264    --  Style_Check_Max_Nesting_Level is True.
 265
 266    -----------------
 267    -- Subprograms --
 268    -----------------
 269
 270    procedure Set_Default_Style_Check_Options;
 271    --  This procedure is called to set the default style checking options in
 272    --  response to a -gnaty switch with no suboptions or from -gnatyy.
 273
 274    procedure Set_GNAT_Style_Check_Options;
 275    --  This procedure is called to set the default style checking options for
 276    --  GNAT units (as set by -gnatg or -gnatyg).
 277
 278    Style_Msg_Buf : String (1 .. 80);
 279    Style_Msg_Len : Natural;
 280    --  Used to return
 281
 282    procedure Set_Style_Check_Options
 283      (Options  : String;
 284       OK       : out Boolean;
 285       Err_Col  : out Natural);
 286    --  This procedure is called to set the style check options that correspond
 287    --  to the characters in the given Options string. If all options are valid,
 288    --  they are set in an additive manner: any previous options are retained
 289    --  unless overridden, unless a minus is encountered, and then subsequent
 290    --  style switches are subtracted from the current set.
 291    --
 292    --  If all options given are valid, then OK is True, Err_Col is set to
 293    --  Options'Last + 1, and Style_Msg_Buf/Style_Msg_Len are unchanged.
 294    --
 295    --  If an invalid character is found, then OK is False on exit, and Err_Col
 296    --  is the index in options of the bad character. In this case Style_Msg_Len
 297    --  is set and Style_Msg_Buf (1 .. Style_Msg_Len) has a detailed message
 298    --  describing the error.
 299
 300    procedure Set_Style_Check_Options (Options : String);
 301    --  Like the above procedure, but used when the Options string is known to
 302    --  be valid. This is for example appropriate for calls where the string ==
 303    --  was obtained by Save_Style_Check_Options.
 304
 305    procedure Reset_Style_Check_Options;
 306    --  Sets all style check options to off
 307
 308    subtype Style_Check_Options is String (1 .. 64);
 309    --  Long enough string to hold all options from Save call below
 310
 311    procedure Save_Style_Check_Options (Options : out Style_Check_Options);
 312    --  Sets Options to represent current selection of options. This set can be
 313    --  restored by first calling Reset_Style_Check_Options, and then calling
 314    --  Set_Style_Check_Options with the Options string.
 315
 316 end Stylesw;