| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT RUN-TIME COMPONENTS -- |
| -- -- |
| -- S Y S T E M . U T F _ 3 2 -- |
| -- -- |
| -- S p e c -- |
| -- -- |
| -- Copyright (C) 2005-2021, Free Software Foundation, Inc. -- |
| -- -- |
| -- GNAT is free software; you can redistribute it and/or modify it under -- |
| -- terms of the GNU General Public License as published by the Free Soft- -- |
| -- ware Foundation; either version 3, or (at your option) any later ver- -- |
| -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- |
| -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- |
| -- or FITNESS FOR A PARTICULAR PURPOSE. -- |
| -- -- |
| -- As a special exception under Section 7 of GPL version 3, you are granted -- |
| -- additional permissions described in the GCC Runtime Library Exception, -- |
| -- version 3.1, as published by the Free Software Foundation. -- |
| -- -- |
| -- You should have received a copy of the GNU General Public License and -- |
| -- a copy of the GCC Runtime Library Exception along with this program; -- |
| -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- |
| -- <http://www.gnu.org/licenses/>. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| -- This package is an internal package that provides basic character |
| -- classification capabilities needed by the compiler for handling full |
| -- 32-bit wide wide characters. We avoid the use of the actual type |
| -- Wide_Wide_Character, since we want to use these routines in the compiler |
| -- itself, and we want to be able to compile the compiler with old versions |
| -- of GNAT that did not implement Wide_Wide_Character. |
| |
| -- System.UTF_32 should not be directly used from an application program, but |
| -- an equivalent package GNAT.UTF_32 can be used directly and provides exactly |
| -- the same services. The reason this package is in System is so that it can |
| -- with'ed by other packages in the Ada and System hierarchies. |
| |
| pragma Compiler_Unit_Warning; |
| |
| package System.UTF_32 is |
| pragma Pure; |
| |
| type UTF_32 is range 0 .. 16#7FFF_FFFF#; |
| -- So far, the only defined character codes are in 0 .. 16#01_FFFF# |
| |
| -- The following type defines the categories from the unicode definitions. |
| -- The one addition we make is Fe, which represents the characters FFFE |
| -- and FFFF in any of the planes. |
| |
| type Category is ( |
| Cc, -- Other, Control |
| Cf, -- Other, Format |
| Cn, -- Other, Not Assigned |
| Co, -- Other, Private Use |
| Cs, -- Other, Surrogate |
| Ll, -- Letter, Lowercase |
| Lm, -- Letter, Modifier |
| Lo, -- Letter, Other |
| Lt, -- Letter, Titlecase |
| Lu, -- Letter, Uppercase |
| Mc, -- Mark, Spacing Combining |
| Me, -- Mark, Enclosing |
| Mn, -- Mark, Nonspacing |
| Nd, -- Number, Decimal Digit |
| Nl, -- Number, Letter |
| No, -- Number, Other |
| Pc, -- Punctuation, Connector |
| Pd, -- Punctuation, Dash |
| Pe, -- Punctuation, Close |
| Pf, -- Punctuation, Final quote |
| Pi, -- Punctuation, Initial quote |
| Po, -- Punctuation, Other |
| Ps, -- Punctuation, Open |
| Sc, -- Symbol, Currency |
| Sk, -- Symbol, Modifier |
| Sm, -- Symbol, Math |
| So, -- Symbol, Other |
| Zl, -- Separator, Line |
| Zp, -- Separator, Paragraph |
| Zs, -- Separator, Space |
| Fe); -- relative position FFFE/FFFF in any plane |
| |
| function Get_Category (U : UTF_32) return Category; |
| -- Given a UTF32 code, returns corresponding Category, or Cn if |
| -- the code does not have an assigned unicode category. |
| |
| -- The following functions perform category tests corresponding to lexical |
| -- classes defined in the Ada standard. There are two interfaces for each |
| -- function. The second takes a Category (e.g. returned by Get_Category). |
| -- The first takes a UTF_32 code. The form taking the UTF_32 code is |
| -- typically more efficient than calling Get_Category, but if several |
| -- different tests are to be performed on the same code, it is more |
| -- efficient to use Get_Category to get the category, then test the |
| -- resulting category. |
| |
| function Is_UTF_32_Letter (U : UTF_32) return Boolean; |
| function Is_UTF_32_Letter (C : Category) return Boolean; |
| pragma Inline (Is_UTF_32_Letter); |
| -- Returns true iff U is a letter that can be used to start an identifier, |
| -- or if C is one of the corresponding categories, which are the following: |
| -- Letter, Uppercase (Lu) |
| -- Letter, Lowercase (Ll) |
| -- Letter, Titlecase (Lt) |
| -- Letter, Modifier (Lm) |
| -- Letter, Other (Lo) |
| -- Number, Letter (Nl) |
| |
| function Is_UTF_32_Digit (U : UTF_32) return Boolean; |
| function Is_UTF_32_Digit (C : Category) return Boolean; |
| pragma Inline (Is_UTF_32_Digit); |
| -- Returns true iff U is a digit that can be used to extend an identifier, |
| -- or if C is one of the corresponding categories, which are the following: |
| -- Number, Decimal_Digit (Nd) |
| |
| function Is_UTF_32_Line_Terminator (U : UTF_32) return Boolean; |
| pragma Inline (Is_UTF_32_Line_Terminator); |
| -- Returns true iff U is an allowed line terminator for source programs, |
| -- if U is in the category Zp (Separator, Paragraph), or Zl (Separator, |
| -- Line), or if U is a conventional line terminator (CR, LF, VT, FF). |
| -- There is no category version for this function, since the set of |
| -- characters does not correspond to a set of Unicode categories. |
| |
| function Is_UTF_32_Mark (U : UTF_32) return Boolean; |
| function Is_UTF_32_Mark (C : Category) return Boolean; |
| pragma Inline (Is_UTF_32_Mark); |
| -- Returns true iff U is a mark character which can be used to extend an |
| -- identifier, or if C is one of the corresponding categories, which are |
| -- the following: |
| -- Mark, Non-Spacing (Mn) |
| -- Mark, Spacing Combining (Mc) |
| |
| function Is_UTF_32_Other (U : UTF_32) return Boolean; |
| function Is_UTF_32_Other (C : Category) return Boolean; |
| pragma Inline (Is_UTF_32_Other); |
| -- Returns true iff U is an other format character, which means that it |
| -- can be used to extend an identifier, but is ignored for the purposes of |
| -- matching of identifiers, or if C is one of the corresponding categories, |
| -- which are the following: |
| -- Other, Format (Cf) |
| |
| function Is_UTF_32_Punctuation (U : UTF_32) return Boolean; |
| function Is_UTF_32_Punctuation (C : Category) return Boolean; |
| pragma Inline (Is_UTF_32_Punctuation); |
| -- Returns true iff U is a punctuation character that can be used to |
| -- separate pieces of an identifier, or if C is one of the corresponding |
| -- categories, which are the following: |
| -- Punctuation, Connector (Pc) |
| |
| function Is_UTF_32_Space (U : UTF_32) return Boolean; |
| function Is_UTF_32_Space (C : Category) return Boolean; |
| pragma Inline (Is_UTF_32_Space); |
| -- Returns true iff U is considered a space to be ignored, or if C is one |
| -- of the corresponding categories, which are the following: |
| -- Separator, Space (Zs) |
| |
| function Is_UTF_32_Non_Graphic (U : UTF_32) return Boolean; |
| function Is_UTF_32_Non_Graphic (C : Category) return Boolean; |
| pragma Inline (Is_UTF_32_Non_Graphic); |
| -- Returns true iff U is considered to be a non-graphic character, or if C |
| -- is one of the corresponding categories, which are the following: |
| -- Other, Control (Cc) |
| -- Other, Private Use (Co) |
| -- Other, Surrogate (Cs) |
| -- Separator, Line (Zl) |
| -- Separator, Paragraph (Zp) |
| -- FFFE or FFFF positions in any plane (Fe) |
| -- |
| -- Note that the Ada category format effector is subsumed by the above |
| -- list of Unicode categories. |
| -- |
| -- Note that Other, Unassigned (Cn) is quite deliberately not included |
| -- in the list of categories above. This means that should any of these |
| -- code positions be defined in future with graphic characters they will |
| -- be allowed without a need to change implementations or the standard. |
| -- |
| -- Note that Other, Format (Cf) is also quite deliberately not included |
| -- in the list of categories above. This means that these characters can |
| -- be included in character and string literals. |
| |
| -- The following function is used to fold to upper case, as required by |
| -- the Ada 2005 standard rules for identifier case folding. Two |
| -- identifiers are equivalent if they are identical after folding all |
| -- letters to upper case using this routine. A corresponding routine to |
| -- fold to lower case is also provided. |
| |
| function Is_UTF_32_NFKC (U : UTF_32) return Boolean; |
| pragma Inline (Is_UTF_32_NFKC); |
| -- Return True if U could be present in a string normalized to |
| -- Normalization Form KC (as defined by Clause 21 of ISO/IEC 10646:2017), |
| -- otherwise returns False. |
| |
| function Is_UTF_32_Basic (U : UTF_32) return Boolean; |
| pragma Inline (Is_UTF_32_Basic); |
| -- Return True if U has no Decomposition Mapping in the code charts of |
| -- ISO/IEC 10646:2017. |
| |
| function UTF_32_To_Lower_Case (U : UTF_32) return UTF_32; |
| pragma Inline (UTF_32_To_Lower_Case); |
| -- If U represents an upper case letter, returns the corresponding lower |
| -- case letter, otherwise U is returned unchanged. The folding rule is |
| -- simply that if the code corresponds to a 10646 entry whose name contains |
| -- the string CAPITAL LETTER, and there is a corresponding entry whose name |
| -- is the same but with CAPITAL LETTER replaced by SMALL LETTER, then the |
| -- code is folded to this SMALL LETTER code. Otherwise the input code is |
| -- returned unchanged. |
| |
| function UTF_32_To_Upper_Case (U : UTF_32) return UTF_32; |
| pragma Inline (UTF_32_To_Upper_Case); |
| -- If U represents a lower case letter, returns the corresponding lower |
| -- case letter, otherwise U is returned unchanged. The folding rule is |
| -- simply that if the code corresponds to a 10646 entry whose name contains |
| -- the string SMALL LETTER, and there is a corresponding entry whose name |
| -- is the same but with SMALL LETTER replaced by CAPITAL LETTER, then the |
| -- code is folded to this CAPITAL LETTER code. Otherwise the input code is |
| -- returned unchanged. |
| |
| function UTF_32_To_Basic (U : UTF_32) return UTF_32; |
| pragma Inline (UTF_32_To_Basic); |
| -- Returns the UTF_32 character whose code point is given by the first |
| -- value of its Decomposition Mapping in the code charts of ISO/IEC |
| -- 10646:2017 if any; returns Item otherwise. |
| |
| end System.UTF_32; |
