remove heading and trailing spaces in tokens in `split` function

[JaroslawWiosna]

split/DatabaseReader.cpp#L34 :

void split (std::string str, std::string splitBy, std::vector<std::string>& tokens) {
    tokens.push_back(str);
    std::size_t splitAt;
    std::size_t splitLen = splitBy.size();
    std::string frag;
    while (true) {
        frag = tokens.back();
    splitAt = frag.find(splitBy);
    if (splitAt == std::string::npos) {
            break;
        }
    tokens.back() = frag.substr(0, splitAt);
    tokens.push_back(frag.substr(splitAt+splitLen, frag.size()-(splitAt+splitLen)));
    }
}

This is an outstanding algorithm, but let's have a look below:

[osboxes@osboxes build]$ gdb ./regionalizer
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Reading symbols from ./regionalizer...done.
(gdb) set args -list ../database/Poland-Cities010-Top10-mock.txt 
(gdb) show args
Argument list to give program being debugged when it is started is "-list ../database/Poland-Cities010-Top10-mock.txt ".
(gdb) break main.cpp:28
Breakpoint 1 at 0x22ce8: file /home/osboxes/github/regionalizer/main.cpp, line 28.
(gdb) run
Starting program: /home/osboxes/github/regionalizer/build/regionalizer -list ../database/Poland-Cities010-Top10-mock.txt 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
printFlags
-list ../database/Poland-Cities010-Top10-mock.txt
Great! ../database/Poland-Cities010-Top10-mock.txt is being processed

Breakpoint 1, main (argc=3, argv=0x7fffffffe698) at /home/osboxes/github/regionalizer/main.cpp:28
28          for (City i : vec) {
(gdb) print i
$1 = {name = "`\033|UUU\000\000ase/Poland-Cities010-Top10-mock.txt", area = 93824994593800, population = 93824992457192, latitude = <error: Cannot access memory at address 0x32>, longitude = <error: Cannot access memory at address 0xd>, 
  distanceToTheFarthest = 93824992465568}
(gdb) n
29              std::cout << i.getAllFields();
(gdb) print i
$2 = {name = "Warsaw ", area = 517, population = 1702139, latitude = " 52.23 ", longitude = " 21.012", distanceToTheFarthest = 0}
(gdb) 

I am talking about the very last line:

name = "Warsaw "

...and there is a trailing space in name field. It looks bad and may cause unpleasant issues in the future.

[kermit10000000]

investigation started

[kermit10000000]

just to be clear. you want the space to be removed only in field name ? because other fields also contains some additional spaces " 52.23 ", longitude = " 21.012". I have checked the code on some examples and i could not reproduce the problem with the split function itself. Looks like the problem is most likely somewhere else.

[kermit10000000]

maybe getAllFields() was causing the problem but now dunno if it did not change over time

[kermit10000000]

I am changing the results of the investigation after consulting better the problem. Now i know it was not about currently existing faults in our outsanding database which is no surprise. It is about the case if have some additional spaces in between "|" signs. But it can be easiely handled by performing function that will do on all the line taken from the database line.replace() replacing all " " with "" until there will be no more left. I will keep working now to prepare that sort of function soon.