split and get next piece

t11e18.nextPiece.cpp

// t11e18.nextPiece.cpp
// juanfc 2023-11-22
// 

#include <iostream>
using namespace std;

string nextPiece(string s, char sep='\0');

int main()
{
    cout << '"' << nextPiece("*abc *cde**fg*", '*') << '"' << endl; // -> ""
    cout << '"' << nextPiece("*abc *cde**fg*") << '"' << endl;      // -> "abc "
    cout << '"' << nextPiece("*abc *cde**fg*") << '"' << endl;      // -> "cde"
    cout << '"' << nextPiece("*abc *cde**fg*") << '"' << endl;      // -> ""
    cout << '"' << nextPiece("*abc *cde**fg*") << '"' << endl;      // -> "fg"
    return 0;
}

string nextPiece(string s, char sep)
{
    static int from;
    static char theSep;
    if (sep != '\0') {
        from = 0;
        theSep = sep;
    }
    string r;
    int i = from;
    while (i < s.length() and s[i] != theSep)
        r += s[i++];
    from = ++i;
    return r;
}