使用STRING_SPLIT时如何处理索引错误

Question

引发GNAT.STRING_SPLIT_INDEX_ERROR

我试着用https://marc.info/?l=gcc-补丁&m＝13902261024587&w＝2。然而，它怎么能读下一行呢。阿达似乎没有类似nextLine((的东西；就像在java中一样。

with Ada.Text_IO;       use Ada.Text_IO;
with GNAT.String_Split; use GNAT.String_Split;
with Ada.Strings.Unbounded; use Ada.Strings.Unbounded;

procedure TextFile is

File   : File_Type;
Tokens : Slice_Set;
Index : Slice_Number;

type Payrate_Type is delta 0.01 range 0.00 .. 1000.00;

type Line_Info is record
Code       : Unbounded_String := Null_Unbounded_String;
Department : Unbounded_String := Null_Unbounded_String;
Name       : Unbounded_String := Null_Unbounded_String;
Title      : Unbounded_String := Null_Unbounded_String;
ID         : Natural :=0;
Payrate    : Payrate_Type:=0.00;
end record;

A_Line : Line_Info;

package Payrate_IO is new Ada.Text_IO.Fixed_IO(Payrate_Type);

Last : Positive;
begin
Open (File, In_File, "Store.txt");
-- Skip the file header
Skip_Line (File);
-- Read the data
while not End_Of_File (File) loop
-- Split the line from the file on array which contains separated
-- words. Treat multiple spaces as a single separator (don't
-- create empty elements).
Create (Tokens, Get_Line (File), " ", Multiple);
-- Print each of the array's values
for I in 1 .. Slice_Count (Tokens) loop
A_Line.Code       := To_Unbounded_String(Slice(Tokens, I));
A_Line.Department := To_Unbounded_String(Slice(Tokens, I+1));
A_Line.Name       := To_Unbounded_String(Slice(Tokens, I+2));
A_Line.Title      := To_Unbounded_String(Slice(Tokens, I+3));
A_Line.ID         := Natural'Value(Slice(Tokens, I+4));
Payrate_IO.Get(Slice(Tokens,I+5),A_Line.Payrate,Last);
end loop;

end loop;

exception
when End_Error =>
if Is_Open(File) then 
Close (File);
end if;
end TextFile;

Store.txt

Code    Department  Name/Vendor  Title          ID      Payrate
IL      Sales       John         Sales_person   1378    25.46
IR      Crew        Jesse        Sales_person   1379    25.46

Answer 1

您的问题不在于未能阅读下一行(Get_Line (File)做得很好(。

有问题

for I in 1 .. Slice_Count (Tokens) loop
A_Line.Code       := To_Unbounded_String(Slice(Tokens, I));
A_Line.Department := To_Unbounded_String(Slice(Tokens, I+1));
A_Line.Name       := To_Unbounded_String(Slice(Tokens, I+2));
A_Line.Title      := To_Unbounded_String(Slice(Tokens, I+3));
A_Line.ID         := Natural'Value(Slice(Tokens, I+4));
Payrate_IO.Get(Slice(Tokens,I+5),A_Line.Payrate,Last);
end loop;

你应该试着向自己解释为什么你有一个循环。

Code在哪个切片中？PayRate在哪个切片中？第二次循环会发生什么？