1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
|
// [[Rcpp::interfaces(r, cpp)]]
#include <RcppSpdlog>
// we accommodate C++20 where fmt::format is available as std::format
// this defines a helper function used below
#if defined(SPDLOG_USE_STD_FORMAT) && __cplusplus >= 202002L
template<std::size_t... S>
std::format_args unpack_vector(const std::vector<std::string>& vec, std::index_sequence<S...>) {
return std::make_format_args(vec[S]...);
}
template<std::size_t size>
std::format_args unpack_vector(const std::vector<std::string>& vec) {
return unpack_vector(vec, std::make_index_sequence<size>());
}
#endif
//' Simple Pass-Through Formatter to \code{fmt::format()}
//'
//' The C-level interface of R does not make it easy to pass \code{...} arguments.
//' This helper function assumes it has already been called with \code{format()}
//' on each argument (as a wrapper can do) so it just spreads out the class to
//' \code{fmt::format{}} which, being C++, uses variadic templates to receive the
//' arguments. The main motivation for this function to able to format string as
//' use by the \sQuote{fmtlib::fmt} library included in \sQuote{spdlog} to write
//' similar debug strings in both R and C++. This function permits R calls with
//' multiple arguments of different types which (by being formatted on the R side)
//' are handled as strings (whereas C++ logging has access to the templating logic).
//'
//' @param s A character variable with a format string for \sQuote{fmtlib::fmt}
//' @param v A character vector with the logging string arguments.
//' @return A single (formatted) string
//' @seealso https://github.com/fmtlib/fmt
// [[Rcpp::export]]
std::string formatter(const std::string s, std::vector<std::string> v) {
size_t n = v.size();
switch (n) {
#if defined(SPDLOG_USE_STD_FORMAT) && __cplusplus >= 202002L
case 0: return std::vformat(std::string_view(s), std::make_format_args());
case 1: return std::vformat(std::string_view(s), unpack_vector<1>(v));
case 2: return std::vformat(std::string_view(s), unpack_vector<2>(v));
case 3: return std::vformat(std::string_view(s), unpack_vector<3>(v));
case 4: return std::vformat(std::string_view(s), unpack_vector<4>(v));
case 5: return std::vformat(std::string_view(s), unpack_vector<5>(v));
case 6: return std::vformat(std::string_view(s), unpack_vector<6>(v));
case 7: return std::vformat(std::string_view(s), unpack_vector<7>(v));
case 8: return std::vformat(std::string_view(s), unpack_vector<8>(v));
case 9: return std::vformat(std::string_view(s), unpack_vector<9>(v));
case 10: return std::vformat(std::string_view(s), unpack_vector<10>(v));
case 11: return std::vformat(std::string_view(s), unpack_vector<11>(v));
case 12: return std::vformat(std::string_view(s), unpack_vector<12>(v));
case 13: return std::vformat(std::string_view(s), unpack_vector<13>(v));
case 14: return std::vformat(std::string_view(s), unpack_vector<14>(v));
case 15: return std::vformat(std::string_view(s), unpack_vector<15>(v));
default: {
Rcpp::warning("Only up to fifteen arguments support for now.");
return std::vformat(std::string_view(s), unpack_vector<12>(v));
}
#else
case 0: return fmt::format(s);
case 1: return fmt::format(s, std::string(v[0]));
case 2: return fmt::format(s, std::string(v[0]), std::string(v[1]));
case 3: return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]));
case 4: return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]), std::string(v[3]));
case 5: return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]), std::string(v[3]), std::string(v[4]));
case 6: return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]), std::string(v[3]), std::string(v[4]), std::string(v[5]));
case 7: return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]), std::string(v[3]), std::string(v[4]), std::string(v[5]), std::string(v[6]));
case 8: return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]), std::string(v[3]), std::string(v[4]), std::string(v[5]), std::string(v[6]), std::string(v[7]));
case 9: return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]), std::string(v[3]), std::string(v[4]), std::string(v[5]), std::string(v[6]), std::string(v[7]), std::string(v[8]));
case 10: return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]), std::string(v[3]), std::string(v[4]), std::string(v[5]), std::string(v[6]), std::string(v[7]), std::string(v[8]), std::string(v[9]));
case 11: return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]), std::string(v[3]), std::string(v[4]), std::string(v[5]), std::string(v[6]), std::string(v[7]), std::string(v[8]), std::string(v[9]), std::string(v[10]));
case 12: return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]), std::string(v[3]), std::string(v[4]), std::string(v[5]), std::string(v[6]), std::string(v[7]), std::string(v[8]), std::string(v[9]), std::string(v[10]), std::string(v[11]));
case 13: return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]), std::string(v[3]), std::string(v[4]), std::string(v[5]), std::string(v[6]), std::string(v[7]), std::string(v[8]), std::string(v[9]), std::string(v[10]), std::string(v[11]), std::string(v[12]));
case 14: return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]), std::string(v[3]), std::string(v[4]), std::string(v[5]), std::string(v[6]), std::string(v[7]), std::string(v[8]), std::string(v[9]), std::string(v[10]), std::string(v[11]), std::string(v[12]), std::string(v[13]));
case 15: return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]), std::string(v[3]), std::string(v[4]), std::string(v[5]), std::string(v[6]), std::string(v[7]), std::string(v[8]), std::string(v[9]), std::string(v[10]), std::string(v[11]), std::string(v[12]), std::string(v[13]), std::string(v[14]));
default: {
Rcpp::warning("Only up to fifteen arguments support for now.");
return fmt::format(s, std::string(v[0]), std::string(v[1]), std::string(v[2]), std::string(v[3]), std::string(v[4]), std::string(v[5]), std::string(v[6]), std::string(v[7]), std::string(v[8]), std::string(v[9]), std::string(v[10]), std::string(v[11]));
}
#endif
}
}
|
