Mixing
Trim whitespace from a String
17
I know there are several ways to do this in Java and C that are nice, but in C++ I can't seem to find a way to easily implement a string trimming function.
This is what I currently have:
string trim(string& str)
{
size_t first = str.find_first_not_of(' ');
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last-first+1));
}
but whenever I try and call
trim(myString);
I get the compiler error
/tmp/ccZZKSEq.o: In function `song::Read(std::basic_ifstream<char,
std::char_traits<char> >&, std::basic_ifstream<char, std::char_traits<char> >&, char const*, char const*)':
song.cpp:(.text+0x31c): undefined reference to `song::trim(std::string&)'
collect2: error: ld returned 1 exit status
I am trying to find a simple and standard way of trimming leading and trailing whitespace from a string without it taking up 100 lines of code, and I tried using regex, but could not get that to work as well.
I also cannot use Boost.
c++ string whitespace trim
edited Oct 23 '17 at 20:40
Joulukuusi
2,15762847
asked Sep 14 '14 at 0:54
kf.kf.
4371520
add a comment |
17
I know there are several ways to do this in Java and C that are nice, but in C++ I can't seem to find a way to easily implement a string trimming function.
This is what I currently have:
string trim(string& str)
{
size_t first = str.find_first_not_of(' ');
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last-first+1));
}
but whenever I try and call
trim(myString);
I get the compiler error
/tmp/ccZZKSEq.o: In function `song::Read(std::basic_ifstream<char,
std::char_traits<char> >&, std::basic_ifstream<char, std::char_traits<char> >&, char const*, char const*)':
song.cpp:(.text+0x31c): undefined reference to `song::trim(std::string&)'
collect2: error: ld returned 1 exit status
I am trying to find a simple and standard way of trimming leading and trailing whitespace from a string without it taking up 100 lines of code, and I tried using regex, but could not get that to work as well.
I also cannot use Boost.
c++ string whitespace trim
edited Oct 23 '17 at 20:40
Joulukuusi
2,15762847
asked Sep 14 '14 at 0:54
kf.kf.
4371520
Issonga namespace? Is it a class?
– K-ballo
Sep 14 '14 at 0:57
1
possible duplicate of Removing leading and trailing spaces from a string
– Anderson Green
Sep 14 '14 at 0:57
3
This question is not really to do with trimming, but with the linking error. Probably you get the same error regardless of the definition of trim
– Brandin
Sep 14 '14 at 0:58
add a comment |
17
17
17
10
I know there are several ways to do this in Java and C that are nice, but in C++ I can't seem to find a way to easily implement a string trimming function.
This is what I currently have:
string trim(string& str)
{
size_t first = str.find_first_not_of(' ');
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last-first+1));
}
but whenever I try and call
trim(myString);
I get the compiler error
/tmp/ccZZKSEq.o: In function `song::Read(std::basic_ifstream<char,
std::char_traits<char> >&, std::basic_ifstream<char, std::char_traits<char> >&, char const*, char const*)':
song.cpp:(.text+0x31c): undefined reference to `song::trim(std::string&)'
collect2: error: ld returned 1 exit status
I am trying to find a simple and standard way of trimming leading and trailing whitespace from a string without it taking up 100 lines of code, and I tried using regex, but could not get that to work as well.
I also cannot use Boost.
c++ string whitespace trim
edited Oct 23 '17 at 20:40
Joulukuusi
2,15762847
asked Sep 14 '14 at 0:54
kf.kf.
4371520
I know there are several ways to do this in Java and C that are nice, but in C++ I can't seem to find a way to easily implement a string trimming function.
This is what I currently have:
string trim(string& str)
{
size_t first = str.find_first_not_of(' ');
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last-first+1));
}
but whenever I try and call
trim(myString);
I get the compiler error
/tmp/ccZZKSEq.o: In function `song::Read(std::basic_ifstream<char,
std::char_traits<char> >&, std::basic_ifstream<char, std::char_traits<char> >&, char const*, char const*)':
song.cpp:(.text+0x31c): undefined reference to `song::trim(std::string&)'
collect2: error: ld returned 1 exit status
I am trying to find a simple and standard way of trimming leading and trailing whitespace from a string without it taking up 100 lines of code, and I tried using regex, but could not get that to work as well.
I also cannot use Boost.
c++ string whitespace trim
c++ string whitespace trim
edited Oct 23 '17 at 20:40
Joulukuusi
2,15762847
asked Sep 14 '14 at 0:54
kf.kf.
4371520
edited Oct 23 '17 at 20:40
Joulukuusi
2,15762847
asked Sep 14 '14 at 0:54
kf.kf.
4371520
edited Oct 23 '17 at 20:40
Joulukuusi
2,15762847
edited Oct 23 '17 at 20:40
Joulukuusi
2,15762847
edited Oct 23 '17 at 20:40
Joulukuusi
2,15762847
2,15762847
asked Sep 14 '14 at 0:54
kf.kf.
4371520
asked Sep 14 '14 at 0:54
kf.kf.
4371520
asked Sep 14 '14 at 0:54
kf.kf.
4371520
4371520
Issonga namespace? Is it a class?
– K-ballo
Sep 14 '14 at 0:57
1
possible duplicate of Removing leading and trailing spaces from a string
– Anderson Green
Sep 14 '14 at 0:57
3
This question is not really to do with trimming, but with the linking error. Probably you get the same error regardless of the definition of trim
– Brandin
Sep 14 '14 at 0:58
add a comment |
Issonga namespace? Is it a class?
– K-ballo
Sep 14 '14 at 0:57
1
possible duplicate of Removing leading and trailing spaces from a string
– Anderson Green
Sep 14 '14 at 0:57
3
This question is not really to do with trimming, but with the linking error. Probably you get the same error regardless of the definition of trim
– Brandin
Sep 14 '14 at 0:58
Is
song a namespace? Is it a class?– K-ballo
Sep 14 '14 at 0:57
Is
song a namespace? Is it a class?– K-ballo
Sep 14 '14 at 0:57
1
1
possible duplicate of Removing leading and trailing spaces from a string
– Anderson Green
Sep 14 '14 at 0:57
possible duplicate of Removing leading and trailing spaces from a string
– Anderson Green
Sep 14 '14 at 0:57
3
3
This question is not really to do with trimming, but with the linking error. Probably you get the same error regardless of the definition of trim
– Brandin
Sep 14 '14 at 0:58
This question is not really to do with trimming, but with the linking error. Probably you get the same error regardless of the definition of trim
– Brandin
Sep 14 '14 at 0:58
add a comment |
5 Answers
5
active
oldest
votes
36
Your code is fine. What you are seeing is a linker issue.
If you put your code in a single file like this:
#include <iostream>
#include <string>
using namespace std;
string trim(const string& str)
{
size_t first = str.find_first_not_of(' ');
if (string::npos == first)
{
return str;
}
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last - first + 1));
}
int main() {
string s = "abc ";
cout << trim(s);
}
then do g++ test.cc and run a.out, you will see it works.
You should check if the file that contains the trim function is included in the link stage of your compilation process.
edited Nov 20 '16 at 22:33
Martin
6,07685065
answered Sep 14 '14 at 1:02
Anthony KongAnthony Kong
15.6k2496176
3
Does it handle""or" "correctly?
– AlexD
Sep 14 '14 at 1:17
4
This gives crashes on empty string!
– Stepan Yakovenko
Nov 14 '15 at 18:58
3
Add 'if (first == string::npos) return "";' to avoid crashing. Besides this it is nice and simple solution. I saw how people using boost (!!!) to implement such things.
– user6416335
Jul 22 '16 at 15:11
string trim(string str)is more move-friendly function signature
– yanpas
May 24 '18 at 13:17
add a comment |
19
Here is how you can do it:
std::string & trim(std::string & str)
{
return ltrim(rtrim(str));
}
And the supportive functions are implemeted as:
std::string & ltrim(std::string & str)
{
auto it2 = std::find_if( str.begin() , str.end() , (char ch){ return !std::isspace<char>(ch , std::locale::classic() ) ; } );
str.erase( str.begin() , it2);
return str;
}
std::string & rtrim(std::string & str)
{
auto it1 = std::find_if( str.rbegin() , str.rend() , (char ch){ return !std::isspace<char>(ch , std::locale::classic() ) ; } );
str.erase( it1.base() , str.end() );
return str;
}
And once you've all these in place, you can write this as well:
std::string trim_copy(std::string const & str)
{
auto s = str;
return ltrim(rtrim(s));
}
Try this
answered Apr 27 '15 at 9:59
gjhagjha
1,318925
1
+1 for introducing the locale which I miss from so many of the other answers around. Not neccessary the correct one as it depends on the application case, but still an important factor when dealing with strings.
– Rado
Aug 30 '17 at 11:14
add a comment |
5
I think that substr() throws an exception if str only contains the whitespace.
I would modify it to the following code:
string trim(string& str)
{
size_t first = str.find_first_not_of(' ');
if (first == std::string::npos)
return "";
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last-first+1));
}
edited Aug 10 '18 at 22:37
Aubin
11.3k64566
answered Oct 14 '15 at 9:49
MartinMartin
5113
This should be right answer
– user6416335
Jul 22 '16 at 15:12
This doesn't work for tabs or other kinds of whitespace besides spaces.
– jocull
Sep 29 '17 at 19:21
@jocull - you are right, but i think its obvious what to do to specify more whitespaces, find_first_not_of(" tnrvf")
– Martin
Feb 6 '18 at 9:38
add a comment |
0
#include <vector>
#include <numeric>
#include <sstream>
#include <iterator>
void Trim(std::string& inputString)
{
std::istringstream stringStream(inputString);
std::vector<std::string> tokens((std::istream_iterator<std::string>(stringStream)), std::istream_iterator<std::string>());
inputString = std::accumulate(std::next(tokens.begin()), tokens.end(),
tokens[0], // start with first element
(std::string a, std::string b) { return a + " " + b; });
}
answered Nov 29 '17 at 14:10
WillWill
11
add a comment |
0
In addition to answer of @gjha:
inline std::string ltrim_copy(const std::string& str)
{
auto it = std::find_if(str.cbegin(), str.cend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return std::string(it, str.cend());
}
inline std::string rtrim_copy(const std::string& str)
{
auto it = std::find_if(str.crbegin(), str.crend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return it == str.crend() ? std::string() : std::string(str.cbegin(), ++it.base());
}
inline std::string trim_copy(const std::string& str)
{
auto it1 = std::find_if(str.cbegin(), str.cend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
if (it1 == str.cend()) {
return std::string();
}
auto it2 = std::find_if(str.crbegin(), str.crend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return it2 == str.crend() ? std::string(it1, str.cend()) : std::string(it1, ++it2.base());
}
answered Jan 2 at 1:26
ivan.ukrivan.ukr
829519
add a comment |
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5 Answers
5
active
oldest
votes
5 Answers
5
active
oldest
votes
active
oldest
votes
active
oldest
votes
36
Your code is fine. What you are seeing is a linker issue.
If you put your code in a single file like this:
#include <iostream>
#include <string>
using namespace std;
string trim(const string& str)
{
size_t first = str.find_first_not_of(' ');
if (string::npos == first)
{
return str;
}
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last - first + 1));
}
int main() {
string s = "abc ";
cout << trim(s);
}
then do g++ test.cc and run a.out, you will see it works.
You should check if the file that contains the trim function is included in the link stage of your compilation process.
edited Nov 20 '16 at 22:33
Martin
6,07685065
answered Sep 14 '14 at 1:02
Anthony KongAnthony Kong
15.6k2496176
3
Does it handle""or" "correctly?
– AlexD
Sep 14 '14 at 1:17
4
This gives crashes on empty string!
– Stepan Yakovenko
Nov 14 '15 at 18:58
3
Add 'if (first == string::npos) return "";' to avoid crashing. Besides this it is nice and simple solution. I saw how people using boost (!!!) to implement such things.
– user6416335
Jul 22 '16 at 15:11
string trim(string str)is more move-friendly function signature
– yanpas
May 24 '18 at 13:17
add a comment |
36
Your code is fine. What you are seeing is a linker issue.
If you put your code in a single file like this:
#include <iostream>
#include <string>
using namespace std;
string trim(const string& str)
{
size_t first = str.find_first_not_of(' ');
if (string::npos == first)
{
return str;
}
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last - first + 1));
}
int main() {
string s = "abc ";
cout << trim(s);
}
then do g++ test.cc and run a.out, you will see it works.
You should check if the file that contains the trim function is included in the link stage of your compilation process.
edited Nov 20 '16 at 22:33
Martin
6,07685065
answered Sep 14 '14 at 1:02
Anthony KongAnthony Kong
15.6k2496176
3
Does it handle""or" "correctly?
– AlexD
Sep 14 '14 at 1:17
4
This gives crashes on empty string!
– Stepan Yakovenko
Nov 14 '15 at 18:58
3
Add 'if (first == string::npos) return "";' to avoid crashing. Besides this it is nice and simple solution. I saw how people using boost (!!!) to implement such things.
– user6416335
Jul 22 '16 at 15:11
string trim(string str)is more move-friendly function signature
– yanpas
May 24 '18 at 13:17
add a comment |
36
36
36
Your code is fine. What you are seeing is a linker issue.
If you put your code in a single file like this:
#include <iostream>
#include <string>
using namespace std;
string trim(const string& str)
{
size_t first = str.find_first_not_of(' ');
if (string::npos == first)
{
return str;
}
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last - first + 1));
}
int main() {
string s = "abc ";
cout << trim(s);
}
then do g++ test.cc and run a.out, you will see it works.
You should check if the file that contains the trim function is included in the link stage of your compilation process.
edited Nov 20 '16 at 22:33
Martin
6,07685065
answered Sep 14 '14 at 1:02
Anthony KongAnthony Kong
15.6k2496176
Your code is fine. What you are seeing is a linker issue.
If you put your code in a single file like this:
#include <iostream>
#include <string>
using namespace std;
string trim(const string& str)
{
size_t first = str.find_first_not_of(' ');
if (string::npos == first)
{
return str;
}
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last - first + 1));
}
int main() {
string s = "abc ";
cout << trim(s);
}
then do g++ test.cc and run a.out, you will see it works.
You should check if the file that contains the trim function is included in the link stage of your compilation process.
edited Nov 20 '16 at 22:33
Martin
6,07685065
answered Sep 14 '14 at 1:02
Anthony KongAnthony Kong
15.6k2496176
edited Nov 20 '16 at 22:33
Martin
6,07685065
edited Nov 20 '16 at 22:33
Martin
6,07685065
edited Nov 20 '16 at 22:33
Martin
6,07685065
6,07685065
answered Sep 14 '14 at 1:02
Anthony KongAnthony Kong
15.6k2496176
answered Sep 14 '14 at 1:02
Anthony KongAnthony Kong
15.6k2496176
answered Sep 14 '14 at 1:02
Anthony KongAnthony Kong
15.6k2496176
15.6k2496176
3
Does it handle""or" "correctly?
– AlexD
Sep 14 '14 at 1:17
4
This gives crashes on empty string!
– Stepan Yakovenko
Nov 14 '15 at 18:58
3
Add 'if (first == string::npos) return "";' to avoid crashing. Besides this it is nice and simple solution. I saw how people using boost (!!!) to implement such things.
– user6416335
Jul 22 '16 at 15:11
string trim(string str)is more move-friendly function signature
– yanpas
May 24 '18 at 13:17
add a comment |
3
Does it handle""or" "correctly?
– AlexD
Sep 14 '14 at 1:17
4
This gives crashes on empty string!
– Stepan Yakovenko
Nov 14 '15 at 18:58
3
Add 'if (first == string::npos) return "";' to avoid crashing. Besides this it is nice and simple solution. I saw how people using boost (!!!) to implement such things.
– user6416335
Jul 22 '16 at 15:11
string trim(string str)is more move-friendly function signature
– yanpas
May 24 '18 at 13:17
3
3
Does it handle
"" or " " correctly?– AlexD
Sep 14 '14 at 1:17
Does it handle
"" or " " correctly?– AlexD
Sep 14 '14 at 1:17
4
4
This gives crashes on empty string!
– Stepan Yakovenko
Nov 14 '15 at 18:58
This gives crashes on empty string!
– Stepan Yakovenko
Nov 14 '15 at 18:58
3
3
Add 'if (first == string::npos) return "";' to avoid crashing. Besides this it is nice and simple solution. I saw how people using boost (!!!) to implement such things.
– user6416335
Jul 22 '16 at 15:11
Add 'if (first == string::npos) return "";' to avoid crashing. Besides this it is nice and simple solution. I saw how people using boost (!!!) to implement such things.
– user6416335
Jul 22 '16 at 15:11
string trim(string str) is more move-friendly function signature– yanpas
May 24 '18 at 13:17
string trim(string str) is more move-friendly function signature– yanpas
May 24 '18 at 13:17
add a comment |
19
Here is how you can do it:
std::string & trim(std::string & str)
{
return ltrim(rtrim(str));
}
And the supportive functions are implemeted as:
std::string & ltrim(std::string & str)
{
auto it2 = std::find_if( str.begin() , str.end() , (char ch){ return !std::isspace<char>(ch , std::locale::classic() ) ; } );
str.erase( str.begin() , it2);
return str;
}
std::string & rtrim(std::string & str)
{
auto it1 = std::find_if( str.rbegin() , str.rend() , (char ch){ return !std::isspace<char>(ch , std::locale::classic() ) ; } );
str.erase( it1.base() , str.end() );
return str;
}
And once you've all these in place, you can write this as well:
std::string trim_copy(std::string const & str)
{
auto s = str;
return ltrim(rtrim(s));
}
Try this
answered Apr 27 '15 at 9:59
gjhagjha
1,318925
1
+1 for introducing the locale which I miss from so many of the other answers around. Not neccessary the correct one as it depends on the application case, but still an important factor when dealing with strings.
– Rado
Aug 30 '17 at 11:14
add a comment |
19
Here is how you can do it:
std::string & trim(std::string & str)
{
return ltrim(rtrim(str));
}
And the supportive functions are implemeted as:
std::string & ltrim(std::string & str)
{
auto it2 = std::find_if( str.begin() , str.end() , (char ch){ return !std::isspace<char>(ch , std::locale::classic() ) ; } );
str.erase( str.begin() , it2);
return str;
}
std::string & rtrim(std::string & str)
{
auto it1 = std::find_if( str.rbegin() , str.rend() , (char ch){ return !std::isspace<char>(ch , std::locale::classic() ) ; } );
str.erase( it1.base() , str.end() );
return str;
}
And once you've all these in place, you can write this as well:
std::string trim_copy(std::string const & str)
{
auto s = str;
return ltrim(rtrim(s));
}
Try this
answered Apr 27 '15 at 9:59
gjhagjha
1,318925
1
+1 for introducing the locale which I miss from so many of the other answers around. Not neccessary the correct one as it depends on the application case, but still an important factor when dealing with strings.
– Rado
Aug 30 '17 at 11:14
add a comment |
19
19
19
Here is how you can do it:
std::string & trim(std::string & str)
{
return ltrim(rtrim(str));
}
And the supportive functions are implemeted as:
std::string & ltrim(std::string & str)
{
auto it2 = std::find_if( str.begin() , str.end() , (char ch){ return !std::isspace<char>(ch , std::locale::classic() ) ; } );
str.erase( str.begin() , it2);
return str;
}
std::string & rtrim(std::string & str)
{
auto it1 = std::find_if( str.rbegin() , str.rend() , (char ch){ return !std::isspace<char>(ch , std::locale::classic() ) ; } );
str.erase( it1.base() , str.end() );
return str;
}
And once you've all these in place, you can write this as well:
std::string trim_copy(std::string const & str)
{
auto s = str;
return ltrim(rtrim(s));
}
Try this
answered Apr 27 '15 at 9:59
gjhagjha
1,318925
Here is how you can do it:
std::string & trim(std::string & str)
{
return ltrim(rtrim(str));
}
And the supportive functions are implemeted as:
std::string & ltrim(std::string & str)
{
auto it2 = std::find_if( str.begin() , str.end() , (char ch){ return !std::isspace<char>(ch , std::locale::classic() ) ; } );
str.erase( str.begin() , it2);
return str;
}
std::string & rtrim(std::string & str)
{
auto it1 = std::find_if( str.rbegin() , str.rend() , (char ch){ return !std::isspace<char>(ch , std::locale::classic() ) ; } );
str.erase( it1.base() , str.end() );
return str;
}
And once you've all these in place, you can write this as well:
std::string trim_copy(std::string const & str)
{
auto s = str;
return ltrim(rtrim(s));
}
Try this
answered Apr 27 '15 at 9:59
gjhagjha
1,318925
edited Aug 18 '15 at 11:13
answered Apr 27 '15 at 9:59
gjhagjha
1,318925
answered Apr 27 '15 at 9:59
gjhagjha
1,318925
answered Apr 27 '15 at 9:59
gjhagjha
1,318925
1,318925
1
+1 for introducing the locale which I miss from so many of the other answers around. Not neccessary the correct one as it depends on the application case, but still an important factor when dealing with strings.
– Rado
Aug 30 '17 at 11:14
add a comment |
1
+1 for introducing the locale which I miss from so many of the other answers around. Not neccessary the correct one as it depends on the application case, but still an important factor when dealing with strings.
– Rado
Aug 30 '17 at 11:14
1
1
+1 for introducing the locale which I miss from so many of the other answers around. Not neccessary the correct one as it depends on the application case, but still an important factor when dealing with strings.
– Rado
Aug 30 '17 at 11:14
+1 for introducing the locale which I miss from so many of the other answers around. Not neccessary the correct one as it depends on the application case, but still an important factor when dealing with strings.
– Rado
Aug 30 '17 at 11:14
add a comment |
5
I think that substr() throws an exception if str only contains the whitespace.
I would modify it to the following code:
string trim(string& str)
{
size_t first = str.find_first_not_of(' ');
if (first == std::string::npos)
return "";
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last-first+1));
}
edited Aug 10 '18 at 22:37
Aubin
11.3k64566
answered Oct 14 '15 at 9:49
MartinMartin
5113
This should be right answer
– user6416335
Jul 22 '16 at 15:12
This doesn't work for tabs or other kinds of whitespace besides spaces.
– jocull
Sep 29 '17 at 19:21
@jocull - you are right, but i think its obvious what to do to specify more whitespaces, find_first_not_of(" tnrvf")
– Martin
Feb 6 '18 at 9:38
add a comment |
5
I think that substr() throws an exception if str only contains the whitespace.
I would modify it to the following code:
string trim(string& str)
{
size_t first = str.find_first_not_of(' ');
if (first == std::string::npos)
return "";
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last-first+1));
}
edited Aug 10 '18 at 22:37
Aubin
11.3k64566
answered Oct 14 '15 at 9:49
MartinMartin
5113
This should be right answer
– user6416335
Jul 22 '16 at 15:12
This doesn't work for tabs or other kinds of whitespace besides spaces.
– jocull
Sep 29 '17 at 19:21
@jocull - you are right, but i think its obvious what to do to specify more whitespaces, find_first_not_of(" tnrvf")
– Martin
Feb 6 '18 at 9:38
add a comment |
5
5
5
I think that substr() throws an exception if str only contains the whitespace.
I would modify it to the following code:
string trim(string& str)
{
size_t first = str.find_first_not_of(' ');
if (first == std::string::npos)
return "";
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last-first+1));
}
edited Aug 10 '18 at 22:37
Aubin
11.3k64566
answered Oct 14 '15 at 9:49
MartinMartin
5113
I think that substr() throws an exception if str only contains the whitespace.
I would modify it to the following code:
string trim(string& str)
{
size_t first = str.find_first_not_of(' ');
if (first == std::string::npos)
return "";
size_t last = str.find_last_not_of(' ');
return str.substr(first, (last-first+1));
}
edited Aug 10 '18 at 22:37
Aubin
11.3k64566
answered Oct 14 '15 at 9:49
MartinMartin
5113
edited Aug 10 '18 at 22:37
Aubin
11.3k64566
edited Aug 10 '18 at 22:37
Aubin
11.3k64566
edited Aug 10 '18 at 22:37
Aubin
11.3k64566
11.3k64566
answered Oct 14 '15 at 9:49
MartinMartin
5113
answered Oct 14 '15 at 9:49
MartinMartin
5113
answered Oct 14 '15 at 9:49
MartinMartin
5113
5113
This should be right answer
– user6416335
Jul 22 '16 at 15:12
This doesn't work for tabs or other kinds of whitespace besides spaces.
– jocull
Sep 29 '17 at 19:21
@jocull - you are right, but i think its obvious what to do to specify more whitespaces, find_first_not_of(" tnrvf")
– Martin
Feb 6 '18 at 9:38
add a comment |
This should be right answer
– user6416335
Jul 22 '16 at 15:12
This doesn't work for tabs or other kinds of whitespace besides spaces.
– jocull
Sep 29 '17 at 19:21
@jocull - you are right, but i think its obvious what to do to specify more whitespaces, find_first_not_of(" tnrvf")
– Martin
Feb 6 '18 at 9:38
This should be right answer
– user6416335
Jul 22 '16 at 15:12
This should be right answer
– user6416335
Jul 22 '16 at 15:12
This doesn't work for tabs or other kinds of whitespace besides spaces.
– jocull
Sep 29 '17 at 19:21
This doesn't work for tabs or other kinds of whitespace besides spaces.
– jocull
Sep 29 '17 at 19:21
@jocull - you are right, but i think its obvious what to do to specify more whitespaces, find_first_not_of(" tnrvf")
– Martin
Feb 6 '18 at 9:38
@jocull - you are right, but i think its obvious what to do to specify more whitespaces, find_first_not_of(" tnrvf")
– Martin
Feb 6 '18 at 9:38
add a comment |
0
#include <vector>
#include <numeric>
#include <sstream>
#include <iterator>
void Trim(std::string& inputString)
{
std::istringstream stringStream(inputString);
std::vector<std::string> tokens((std::istream_iterator<std::string>(stringStream)), std::istream_iterator<std::string>());
inputString = std::accumulate(std::next(tokens.begin()), tokens.end(),
tokens[0], // start with first element
(std::string a, std::string b) { return a + " " + b; });
}
answered Nov 29 '17 at 14:10
WillWill
11
add a comment |
0
#include <vector>
#include <numeric>
#include <sstream>
#include <iterator>
void Trim(std::string& inputString)
{
std::istringstream stringStream(inputString);
std::vector<std::string> tokens((std::istream_iterator<std::string>(stringStream)), std::istream_iterator<std::string>());
inputString = std::accumulate(std::next(tokens.begin()), tokens.end(),
tokens[0], // start with first element
(std::string a, std::string b) { return a + " " + b; });
}
answered Nov 29 '17 at 14:10
WillWill
11
add a comment |
0
0
0
#include <vector>
#include <numeric>
#include <sstream>
#include <iterator>
void Trim(std::string& inputString)
{
std::istringstream stringStream(inputString);
std::vector<std::string> tokens((std::istream_iterator<std::string>(stringStream)), std::istream_iterator<std::string>());
inputString = std::accumulate(std::next(tokens.begin()), tokens.end(),
tokens[0], // start with first element
(std::string a, std::string b) { return a + " " + b; });
}
answered Nov 29 '17 at 14:10
WillWill
11
#include <vector>
#include <numeric>
#include <sstream>
#include <iterator>
void Trim(std::string& inputString)
{
std::istringstream stringStream(inputString);
std::vector<std::string> tokens((std::istream_iterator<std::string>(stringStream)), std::istream_iterator<std::string>());
inputString = std::accumulate(std::next(tokens.begin()), tokens.end(),
tokens[0], // start with first element
(std::string a, std::string b) { return a + " " + b; });
}
answered Nov 29 '17 at 14:10
WillWill
11
answered Nov 29 '17 at 14:10
WillWill
11
answered Nov 29 '17 at 14:10
WillWill
11
answered Nov 29 '17 at 14:10
WillWill
11
11
add a comment |
add a comment |
0
In addition to answer of @gjha:
inline std::string ltrim_copy(const std::string& str)
{
auto it = std::find_if(str.cbegin(), str.cend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return std::string(it, str.cend());
}
inline std::string rtrim_copy(const std::string& str)
{
auto it = std::find_if(str.crbegin(), str.crend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return it == str.crend() ? std::string() : std::string(str.cbegin(), ++it.base());
}
inline std::string trim_copy(const std::string& str)
{
auto it1 = std::find_if(str.cbegin(), str.cend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
if (it1 == str.cend()) {
return std::string();
}
auto it2 = std::find_if(str.crbegin(), str.crend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return it2 == str.crend() ? std::string(it1, str.cend()) : std::string(it1, ++it2.base());
}
answered Jan 2 at 1:26
ivan.ukrivan.ukr
829519
add a comment |
0
In addition to answer of @gjha:
inline std::string ltrim_copy(const std::string& str)
{
auto it = std::find_if(str.cbegin(), str.cend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return std::string(it, str.cend());
}
inline std::string rtrim_copy(const std::string& str)
{
auto it = std::find_if(str.crbegin(), str.crend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return it == str.crend() ? std::string() : std::string(str.cbegin(), ++it.base());
}
inline std::string trim_copy(const std::string& str)
{
auto it1 = std::find_if(str.cbegin(), str.cend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
if (it1 == str.cend()) {
return std::string();
}
auto it2 = std::find_if(str.crbegin(), str.crend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return it2 == str.crend() ? std::string(it1, str.cend()) : std::string(it1, ++it2.base());
}
answered Jan 2 at 1:26
ivan.ukrivan.ukr
829519
add a comment |
0
0
0
In addition to answer of @gjha:
inline std::string ltrim_copy(const std::string& str)
{
auto it = std::find_if(str.cbegin(), str.cend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return std::string(it, str.cend());
}
inline std::string rtrim_copy(const std::string& str)
{
auto it = std::find_if(str.crbegin(), str.crend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return it == str.crend() ? std::string() : std::string(str.cbegin(), ++it.base());
}
inline std::string trim_copy(const std::string& str)
{
auto it1 = std::find_if(str.cbegin(), str.cend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
if (it1 == str.cend()) {
return std::string();
}
auto it2 = std::find_if(str.crbegin(), str.crend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return it2 == str.crend() ? std::string(it1, str.cend()) : std::string(it1, ++it2.base());
}
answered Jan 2 at 1:26
ivan.ukrivan.ukr
829519
In addition to answer of @gjha:
inline std::string ltrim_copy(const std::string& str)
{
auto it = std::find_if(str.cbegin(), str.cend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return std::string(it, str.cend());
}
inline std::string rtrim_copy(const std::string& str)
{
auto it = std::find_if(str.crbegin(), str.crend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return it == str.crend() ? std::string() : std::string(str.cbegin(), ++it.base());
}
inline std::string trim_copy(const std::string& str)
{
auto it1 = std::find_if(str.cbegin(), str.cend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
if (it1 == str.cend()) {
return std::string();
}
auto it2 = std::find_if(str.crbegin(), str.crend(),
(char ch) { return !std::isspace<char>(ch, std::locale::classic()); });
return it2 == str.crend() ? std::string(it1, str.cend()) : std::string(it1, ++it2.base());
}
answered Jan 2 at 1:26
ivan.ukrivan.ukr
829519
edited Jan 2 at 1:31
answered Jan 2 at 1:26
ivan.ukrivan.ukr
829519
answered Jan 2 at 1:26
ivan.ukrivan.ukr
829519
answered Jan 2 at 1:26
ivan.ukrivan.ukr
829519
829519
add a comment |
add a comment |
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Is
songa namespace? Is it a class?– K-ballo
Sep 14 '14 at 0:57
1
possible duplicate of Removing leading and trailing spaces from a string
– Anderson Green
Sep 14 '14 at 0:57
3
This question is not really to do with trimming, but with the linking error. Probably you get the same error regardless of the definition of trim
– Brandin
Sep 14 '14 at 0:58