Prefer suitable abstractions to direct use of language features

Reason

A "suitable abstraction" (e.g., library or class) is closer to the application concepts than the bare language, leads to shorter and clearer code, and is likely to be better tested.

Example

vector<string> read1(istream& is)   // good
{
    vector<string> res;
    for (string s; is >> s;)
        res.push_back(s);
    return res;
}

The more traditional and lower-level near-equivalent is longer, messier, harder to get right, and most likely slower:

char** read2(istream& is, int maxelem, int maxstring, int* nread)   // bad: verbose and incomplete
{
    auto res = new char*[maxelem];
    int elemcount = 0;
    while (is && elemcount < maxelem) {
        auto s = new char[maxstring];
        is.read(s, maxstring);
        res[elemcount++] = s;
    }
    *nread = elemcount;
    return res;
}

Once the checking for overflow and error handling has been added that code gets quite messy, and there is the problem remembering to delete the returned pointer and the C-style strings that array contains.

Enforcement

Not easy. ??? Look for messy loops, nested loops, long functions, absence of function calls, lack of use of built-in types. Cyclomatic complexity?