我正在阅读一个简单的文本文件。一切都按其应有的方式工作,除非遇到开括号(“[”)字符。然后我得到一个 CONSTRAINT_ERROR。
我的职能是:
----------------------------------------------
-- GET_FILE_CONTENTS
function Get_File_Contents (File_Name : in String)
return String_Array is
-- Loads the entire file into a dynamically sized
-- array of Unbounded_Wide_String.
-- The line count is used to dynamically size the array.
Line_Count : Natural
:= 0;
File : Ada.Wide_Text_IO.File_Type;
begin
-- Get the line count before opening the file.
Line_Count := Get_File_Line_Count (File_Name);
Ada.Wide_Text_IO.Open (File,
In_File,
File_Name);
declare
Lines : String_Array (1 .. Line_Count);
begin
-- Step through the file and save each line.
for Current_Line in reverse 1 .. Line_Count loop
Lines(Current_Line) := To_Unbounded_Wide_String (Ada.Wide_Text_IO.Get_Line (File));
end loop;
-- Remember to close the file.
Ada.Wide_Text_IO.Close (File);
return Lines;
end;
end Get_File_Contents;
CONSTRAINT_ERROR 在“s-wchcnv.adb:207”中引发。文件的相关部分是这样的
when WCEM_Brackets =>
if C /= '[' then
return Character'Pos (C);
end if;
if In_Char /= '"' then
raise Constraint_Error; <======= CONSTRAINT_ERROR
end if;
这是我找到的信息:
-- Note on the use of brackets encoding (WCEM_Brackets). The brackets
-- encoding method is ambiguous in the context of this function, since
-- there is no way to tell if ["1234"] is eight unencoded characters or
-- one encoded character. In the context of Ada sources, any sequence
-- starting [" must be the start of an encoding (since that sequence is
-- not valid in Ada source otherwise). The routines in this package use
-- the same approach. If the input string contains the sequence [" then
-- this is assumed to be the start of a brackets encoding sequence, and
-- if it does not match the syntax, an error is raised.
如何关闭此功能,以便“[”不会被解释为 WCEM?
Edit:
编译器版本为GNAT GPL 2014 (20140331)
操作系统是 Windows 7 x64
重现 CONSTRAINT_ERROR 的小程序:
with Ada.Wide_Text_IO; use Ada.Wide_Text_IO;
procedure Main is
File : File_Type;
File_Name : String := "Data.txt";
begin
Open (File,
In_File,
File_Name);
while not End_Of_File (File) loop
declare
Line : Wide_String := Get_Line (File);
begin
Put_Line (Line);
end;
end loop;
Close (File);
end Main;
“Data.txt”文件需要位于可执行文件附近。
如果“Data.txt”包含如下文本,没问题。
Hello
abc
添加“[”并引发 CONSTRAINT_ERROR:
Hello[
abc