@ssnl would it be more elegant to do this with std::regex?

To make regex work, we would have to account for future/other device types (ROCM?, etc.). I wasn't sure how to do that properly... So I kept stoi.

You could do something with regex groups, like the following so that we don't hardcode cpu & cuda:

#include <iostream>
#include <regex>

int main()
{
    static const std::regex with_idx_regex("([a-zA-Z_]+):([0-9]+)");
    static const std::regex without_idx_regex("([a-zA-Z_]+)");

    std::smatch match;
    const std::string device_string = "cuda:1";
    const bool ok = std::regex_match(device_string, match, with_idx_regex);
    if (ok) {
        std::cout << "device: " << match[1].str() << std::endl;
        std::cout << "idx: " << match[2].str() << std::endl;
    }   
}

The regex-based approach will probably have different error messages from the current parsing based approach, but it's a lot nicer than having to maintain our own parser for this

using regex now!

friendly ping :) @zou3519

Thanks! I'll take a look by eod tomorrow

I'm getting "error: no member named 'invalid_argument' in namespace 'std'
throw std::invalid_argument("Not an integer");" on some of the internal builds. As far as I can tell we don't need to throw nice errors here, so do you think it would be fine to remove these?

Alternatively we could try to include <stdexcept> but I'm not really sure what the downstream ramifications of that are

Let's try including stdexcept! Without this check stoi(empty_string) would succeed.