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Diffstat (limited to 'gcc/ada/libgnat/s-regexp.ads')
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diff --git a/gcc/ada/libgnat/s-regexp.ads b/gcc/ada/libgnat/s-regexp.ads new file mode 100644 index 0000000..0155b43 --- /dev/null +++ b/gcc/ada/libgnat/s-regexp.ads @@ -0,0 +1,141 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- S Y S T E M . R E G E X P -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 1998-2017, AdaCore -- +-- -- +-- 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. -- +-- -- +------------------------------------------------------------------------------ + +-- Simple Regular expression matching + +-- This package provides a simple implementation of a regular expression +-- pattern matching algorithm, using a subset of the syntax of regular +-- expressions copied from familiar Unix style utilities. + +-- Note: this package is in the System hierarchy so that it can be directly +-- be used by other predefined packages. User access to this package is via +-- a renaming of this package in GNAT.Regexp (file g-regexp.ads). + +with Ada.Finalization; + +package System.Regexp is + + -- The regular expression must first be compiled, using the Compile + -- function, which creates a finite state matching table, allowing + -- very fast matching once the expression has been compiled. + + -- The following is the form of a regular expression, expressed in Ada + -- reference manual style BNF is as follows + + -- regexp ::= term + + -- regexp ::= term | term -- alternation (term or term ...) + + -- term ::= item + + -- term ::= item item ... -- concatenation (item then item) + + -- item ::= elmt -- match elmt + -- item ::= elmt * -- zero or more elmt's + -- item ::= elmt + -- one or more elmt's + -- item ::= elmt ? -- matches elmt or nothing + + -- elmt ::= nchr -- matches given character + -- elmt ::= [nchr nchr ...] -- matches any character listed + -- elmt ::= [^ nchr nchr ...] -- matches any character not listed + -- elmt ::= [char - char] -- matches chars in given range + -- elmt ::= . -- matches any single character + -- elmt ::= ( regexp ) -- parens used for grouping + + -- char ::= any character, including special characters + -- nchr ::= any character except \()[].*+?^ or \char to match char + -- ... is used to indication repetition (one or more terms) + + -- See also regexp(1) man page on Unix systems for further details + + -- A second kind of regular expressions is provided. This one is more + -- like the wild card patterns used in file names by the Unix shell (or + -- DOS prompt) command lines. The grammar is the following: + + -- regexp ::= term + + -- term ::= elmt + -- term ::= elmt elmt ... -- concatenation (elmt then elmt) + -- term ::= {elmt, elmt, ...} -- alternation (matches any of elmt) + + -- elmt ::= * -- any string of 0 or more characters + -- elmt ::= ? -- matches any character + -- elmt ::= char + -- elmt ::= [^ char char ...] -- matches any character not listed + -- elmt ::= [char char ...] -- matches any character listed + -- elmt ::= [char - char] -- matches any character in given range + + -- \char is also supported by this grammar. + + -- Important note : This package was mainly intended to match regular + -- expressions against file names. The whole string has to match the + -- regular expression. If only a substring matches, then the function + -- Match will return False. + + type Regexp is private; + -- Private type used to represent a regular expression + + Error_In_Regexp : exception; + -- Exception raised when an error is found in the regular expression + + function Compile + (Pattern : String; + Glob : Boolean := False; + Case_Sensitive : Boolean := True) return Regexp; + -- Compiles a regular expression S. If the syntax of the given + -- expression is invalid (does not match above grammar), Error_In_Regexp + -- is raised. If Glob is True, the pattern is considered as a 'globbing + -- pattern', that is a pattern as given by the second grammar above. + -- As a special case, if Pattern is the empty string it will always + -- match. + + function Match (S : String; R : Regexp) return Boolean; + -- True if S matches R, otherwise False. Raises Constraint_Error if + -- R is an uninitialized regular expression value. + +private + type Regexp_Value; + + type Regexp_Access is access Regexp_Value; + + type Regexp is new Ada.Finalization.Controlled with record + R : Regexp_Access := null; + end record; + + pragma Finalize_Storage_Only (Regexp); + + procedure Finalize (R : in out Regexp); + -- Free the memory occupied by R + + procedure Adjust (R : in out Regexp); + -- Called after an assignment (do a copy of the Regexp_Access.all) + +end System.Regexp; |