fmt_slow_for_u32.md

msvc results:

ns/op	op/s	err%	total	Random u32 to base 10. w/ /utf-8
2.71	369,270,304.57	1.4%	0.00	null, i.e. the rng perf
6.98	143,213,409.65	1.6%	0.00	jeaiii::to_text
9.63	103,842,159.92	0.4%	0.01	fmt::format_int
21.46	46,606,363.07	2.0%	0.01	std::to_string
21.56	46,372,782.63	1.1%	0.01	std::to_chars
54.56	18,329,649.17	1.0%	0.03	std::sprintf
576.23	1,735,415.94	0.8%	0.35	std::ostringstream
481.76	2,075,704.25	0.7%	0.29	std::ostrstream
39.96	25,027,285.13	1.5%	0.02	fmt::format
17.18	58,199,071.27	1.4%	0.01	fmt::format - FMT_COMPILE
20.13	49,683,860.23	1.1%	0.01	fmt::format_to
10.64	93,941,234.41	1.6%	0.01	fmt::format_to - FMT_COMPILE
7.99	125,156,445.56	0.3%	0.00	fast_io::print_reserve_define
10.33	96,843,891.40	0.6%	0.01	fast_io::concat
90.93	10,997,356.26	0.6%	0.06	std::format
51.58	19,387,174.36	0.3%	0.03	std::format_to

Clang-cl results:

ns/op	op/s	err%	total	Random u32 to base 10. w/ /utf-8
2.46	407,325,581.40	0.0%	0.00	null, i.e. the rng perf
5.73	174,570,458.40	0.2%	0.00	jeaiii::to_text
9.66	103,548,163.55	0.5%	0.01	fmt::format_int
17.55	56,978,369.38	0.4%	0.01	std::to_string
14.33	69,767,329.13	0.5%	0.01	std::to_chars
54.00	18,518,714.32	1.0%	0.03	std::sprintf
558.16	1,791,589.81	2.2%	0.34	std::ostringstream
475.49	2,103,103.93	1.4%	0.29	std::ostrstream
29.76	33,597,568.95	2.8%	0.02	fmt::format
15.27	65,500,063.70	3.0%	0.01	fmt::format - FMT_COMPILE
17.48	57,196,068.80	0.6%	0.01	fmt::format_to
8.59	116,348,557.15	1.1%	0.01	fmt::format_to - FMT_COMPILE
5.83	171,609,195.40	0.6%	0.00	fast_io::print_reserve_define
9.30	107,517,503.50	0.3%	0.01	fast_io::concat

Notes:

• When a function returns an std::string, I copy [result.begin(), result.end()] to an other buffer to emulate string assignement.
• this was ran on a ryzen 3700x if that helps you for stuff