1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT RUN-TIME COMPONENTS                         --
4--                                                                          --
5--          A D A . W I D E _ C H A R A C T E R S . U N I C O D E           --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--          Copyright (C) 2005-2012, 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.                                     --
17--                                                                          --
18-- As a special exception under Section 7 of GPL version 3, you are granted --
19-- additional permissions described in the GCC Runtime Library Exception,   --
20-- version 3.1, as published by the Free Software Foundation.               --
21--                                                                          --
22-- You should have received a copy of the GNU General Public License and    --
23-- a copy of the GCC Runtime Library Exception along with this program;     --
24-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
25-- <http://www.gnu.org/licenses/>.                                          --
26--                                                                          --
27-- GNAT was originally developed  by the GNAT team at  New York University. --
28-- Extensive contributions were provided by Ada Core Technologies Inc.      --
29--                                                                          --
30------------------------------------------------------------------------------
31
32--  Unicode categorization routines for Wide_Character. Note that this
33--  package is strictly speaking Ada 2005 (since it is a child of an
34--  Ada 2005 unit), but we make it available in Ada 95 mode, since it
35--  only deals with wide characters.
36
37with System.UTF_32;
38
39package Ada.Wide_Characters.Unicode is
40   pragma Pure;
41
42   --  The following type defines the categories from the unicode definitions.
43   --  The one addition we make is Fe, which represents the characters FFFE
44   --  and FFFF in any of the planes.
45
46   type Category is new System.UTF_32.Category;
47   --  Cc   Other, Control
48   --  Cf   Other, Format
49   --  Cn   Other, Not Assigned
50   --  Co   Other, Private Use
51   --  Cs   Other, Surrogate
52   --  Ll   Letter, Lowercase
53   --  Lm   Letter, Modifier
54   --  Lo   Letter, Other
55   --  Lt   Letter, Titlecase
56   --  Lu   Letter, Uppercase
57   --  Mc   Mark, Spacing Combining
58   --  Me   Mark, Enclosing
59   --  Mn   Mark, Nonspacing
60   --  Nd   Number, Decimal Digit
61   --  Nl   Number, Letter
62   --  No   Number, Other
63   --  Pc   Punctuation, Connector
64   --  Pd   Punctuation, Dash
65   --  Pe   Punctuation, Close
66   --  Pf   Punctuation, Final quote
67   --  Pi   Punctuation, Initial quote
68   --  Po   Punctuation, Other
69   --  Ps   Punctuation, Open
70   --  Sc   Symbol, Currency
71   --  Sk   Symbol, Modifier
72   --  Sm   Symbol, Math
73   --  So   Symbol, Other
74   --  Zl   Separator, Line
75   --  Zp   Separator, Paragraph
76   --  Zs   Separator, Space
77   --  Fe   relative position FFFE/FFFF in plane
78
79   function Get_Category (U : Wide_Character) return Category;
80   pragma Inline (Get_Category);
81   --  Given a Wide_Character, returns corresponding Category, or Cn if the
82   --  code does not have an assigned unicode category.
83
84   --  The following functions perform category tests corresponding to lexical
85   --  classes defined in the Ada standard. There are two interfaces for each
86   --  function. The second takes a Category (e.g. returned by Get_Category).
87   --  The first takes a Wide_Character. The form taking the Wide_Character is
88   --  typically more efficient than calling Get_Category, but if several
89   --  different tests are to be performed on the same code, it is more
90   --  efficient to use Get_Category to get the category, then test the
91   --  resulting category.
92
93   function Is_Letter (U : Wide_Character) return Boolean;
94   function Is_Letter (C : Category)       return Boolean;
95   pragma Inline (Is_Letter);
96   --  Returns true iff U is a letter that can be used to start an identifier,
97   --  or if C is one of the corresponding categories, which are the following:
98   --    Letter, Uppercase (Lu)
99   --    Letter, Lowercase (Ll)
100   --    Letter, Titlecase (Lt)
101   --    Letter, Modifier  (Lm)
102   --    Letter, Other     (Lo)
103   --    Number, Letter    (Nl)
104
105   function Is_Digit (U : Wide_Character) return Boolean;
106   function Is_Digit (C : Category)       return Boolean;
107   pragma Inline (Is_Digit);
108   --  Returns true iff U is a digit that can be used to extend an identifer,
109   --  or if C is one of the corresponding categories, which are the following:
110   --    Number, Decimal_Digit (Nd)
111
112   function Is_Line_Terminator (U : Wide_Character) return Boolean;
113   pragma Inline (Is_Line_Terminator);
114   --  Returns true iff U is an allowed line terminator for source programs,
115   --  if U is in the category Zp (Separator, Paragaph), or Zs (Separator,
116   --  Line), or if U is a conventional line terminator (CR, LF, VT, FF).
117   --  There is no category version for this function, since the set of
118   --  characters does not correspond to a set of Unicode categories.
119
120   function Is_Mark (U : Wide_Character) return Boolean;
121   function Is_Mark (C : Category)       return Boolean;
122   pragma Inline (Is_Mark);
123   --  Returns true iff U is a mark character which can be used to extend an
124   --  identifier, or if C is one of the corresponding categories, which are
125   --  the following:
126   --    Mark, Non-Spacing (Mn)
127   --    Mark, Spacing Combining (Mc)
128
129   function Is_Other (U : Wide_Character) return Boolean;
130   function Is_Other (C : Category)       return Boolean;
131   pragma Inline (Is_Other);
132   --  Returns true iff U is an other format character, which means that it
133   --  can be used to extend an identifier, but is ignored for the purposes of
134   --  matching of identiers, or if C is one of the corresponding categories,
135   --  which are the following:
136   --    Other, Format (Cf)
137
138   function Is_Punctuation (U : Wide_Character) return Boolean;
139   function Is_Punctuation (C : Category)       return Boolean;
140   pragma Inline (Is_Punctuation);
141   --  Returns true iff U is a punctuation character that can be used to
142   --  separate pices of an identifier, or if C is one of the corresponding
143   --  categories, which are the following:
144   --    Punctuation, Connector (Pc)
145
146   function Is_Space (U : Wide_Character) return Boolean;
147   function Is_Space (C : Category)       return Boolean;
148   pragma Inline (Is_Space);
149   --  Returns true iff U is considered a space to be ignored, or if C is one
150   --  of the corresponding categories, which are the following:
151   --    Separator, Space (Zs)
152
153   function Is_Non_Graphic (U : Wide_Character) return Boolean;
154   function Is_Non_Graphic (C : Category)       return Boolean;
155   pragma Inline (Is_Non_Graphic);
156   --  Returns true iff U is considered to be a non-graphic character, or if C
157   --  is one of the corresponding categories, which are the following:
158   --    Other, Control (Cc)
159   --    Other, Private Use (Co)
160   --    Other, Surrogate (Cs)
161   --    Separator, Line (Zl)
162   --    Separator, Paragraph (Zp)
163   --    FFFE or FFFF positions in any plane (Fe)
164   --
165   --  Note that the Ada category format effector is subsumed by the above
166   --  list of Unicode categories.
167   --
168   --  Note that Other, Unassiged (Cn) is quite deliberately not included
169   --  in the list of categories above. This means that should any of these
170   --  code positions be defined in future with graphic characters they will
171   --  be allowed without a need to change implementations or the standard.
172   --
173   --  Note that Other, Format (Cf) is also quite deliberately not included
174   --  in the list of categories above. This means that these characters can
175   --  be included in character and string literals.
176
177   --  The following function is used to fold to upper case, as required by
178   --  the Ada 2005 standard rules for identifier case folding. Two
179   --  identifiers are equivalent if they are identical after folding all
180   --  letters to upper case using this routine. A corresponding function to
181   --  fold to lower case is also provided.
182
183   function To_Lower_Case (U : Wide_Character) return Wide_Character;
184   pragma Inline (To_Lower_Case);
185   --  If U represents an upper case letter, returns the corresponding lower
186   --  case letter, otherwise U is returned unchanged. The folding is locale
187   --  independent as defined by documents referenced in the note in section
188   --  1 of ISO/IEC 10646:2003
189
190   function To_Upper_Case (U : Wide_Character) return Wide_Character;
191   pragma Inline (To_Upper_Case);
192   --  If U represents a lower case letter, returns the corresponding upper
193   --  case letter, otherwise U is returned unchanged. The folding is locale
194   --  independent as defined by documents referenced in the note in section
195   --  1 of ISO/IEC 10646:2003
196
197end Ada.Wide_Characters.Unicode;
198