string tips

Anyone got a good way to do this without having to use a c-string (and <cstring>):

Code:

#include <iostream>
#include <string>
#include <cstring>
using namespace std;

void stripWS(string &str) {
	int len = str.size();
	char copy[len+1], *p;
	strcpy(copy,str.c_str());
	p = &copy[len-1];
	while (*p == ' ' || *p == '\t') *(p--) = '\0';
	p = copy;
	while (*p == ' ' || *p == '\t') *p++;
	str = p;
}


int main() {
	string test("\t\t so what\t   ");

	cout << "->" << test << "<-\n";
	stripWS(test);
	cout << "->" << test << "<-\n";

	return 0;
}

I have not tested it, but perhaps something like this will work:

Code:

void stripWS(string& str) {
    const string::size_type first = str.find_first_not_of(" \t");
    if (first != string::npos)
    {
        const string::size_type last = str.find_last_not_of(" \t");
        str = str.substr(first, last - first + 1);
    }
    else
    {
        str.clear(); // The string only comprises of whitespace.
    }
}

Yeah, that's the kind of thing I was thinking of. Seems to work too. Thanks!