Remove JSON Dependency #1812
Remove JSON Dependency #1812
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| json parse_json(char* s, int length) { | ||
| membuf sbuf(s, length); | ||
| std::istream stream(&sbuf); | ||
| std::string os(s, length); |
| return result; | ||
| } | ||
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| struct membuf : std::streambuf { |
| s >> std::ws >> ch; | ||
| if (ch == '}') { | ||
| break; | ||
| } else if (ch != ',') { |
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I think this is something that can be fixed later but unfortunately this is a tiny bit out of spec. It is also one of the most annoying parts of the json spec so I don't really mind if we don't fix it immediately but we should at least put a TODO unfortunately.
The following is unfortunately not valid JSON ["a", "b",] (notice the extra comma) but it would be parsed without error here. Both for object and array.
| std::string str = ""; | ||
| for (int i = 0; i < 3; i++) { | ||
| str += s.get(); | ||
| } | ||
| if (str != "ull") { |
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| std::string str = ""; | |
| for (int i = 0; i < 3; i++) { | |
| str += s.get(); | |
| } | |
| if (str != "ull") { | |
| char buff[3] = {0}; | |
| if (s.read(buff, 3); !std::equal(buff, buff+3, "ull")) { |
This is a total nitpick but the string may do a heap allocation there (may even do more than 1 given the +=) and it really is just to check 3 characters so I think it is a bit of a an overkill. You could even do if (s.get() != 'u' || s.get() != 'l' || s.get() != 'l') {...
| if (num.find_first_of(".eE") != std::string::npos) { | ||
| return json(std::stod(num)); | ||
| } else { | ||
| return json(std::stol(num)); | ||
| } |
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| if (num.find_first_of(".eE") != std::string::npos) { | |
| return json(std::stod(num)); | |
| } else { | |
| return json(std::stol(num)); | |
| } | |
| size_t pos; | |
| json ret; | |
| if (num.find_first_of(".eE") != std::string::npos) { | |
| ret = json(std::stod(num, &pos)); | |
| } else { | |
| ret = json(std::stol(num, &pos)); | |
| } | |
| if (pos != num.size()) { | |
| throw std::invalid_argument(...); | |
| } | |
| return std::move(ret); |
The above is a bit of a problem because read_digits reads any character in [0-9-eE.] which means it could be not a number eg 1.2.3.4 and in this case we should fail. std::stod and friends return the number of characters processed so it is a fairly easy change to check for correctness.
A basic JSON parser that allows us to remove the nlohmann/json dependency.
Should be pretty much complete with the exception of unicode support.