Update "how it works" section

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Clyne 4 years ago committed by GitHub
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@ -27,22 +27,26 @@ Try it [on Compiler Explorer](https://godbolt.org/z/T-MFoh).
The basic structure of `to_string` is shown below:
```cpp
template<auto N, unsigned int base, /* N type-check and base bounds-check */>
template<auto N, unsigned int base, typename char_type, /* N type-check and base bounds-check */>
struct to_string_t {
char buf[]; // Size selection explained later.
constexpr to_string_t() {} // Converts the integer to a string stored in buf.
constexpr operator char *() {} // These allow for the object to be implicitly converted
constexpr operator const char *() {} // to a character pointer.
char_type buf[]; // Size selection explained later.
constexpr to_string_t() {} // Converts the integer to a string stored in buf.
constexpr operator char_type *() {} // These allow for the object to be implicitly converted
constexpr operator const char_type *() {} // to a character pointer.
// begin() and end() are supported too.
};
template<auto N, unsigned int base = 10>
to_string_t<N, base> to_string; // Simplifies usage: to_string_t<N, base>() becomes to_string<N, base>.
template<auto N, unsigned int base = 10, typename char_type = char>
constexpr to_string_t<N, base, char_type> to_string; // Simplifies usage, e.g. to_string_t<367>() becomes to_string<367>.
```
Since the number and base are template parameters, each differing `to_string` use will get its own character buffer.
The integer/string conversion is done using a simple method I learned over the years, where the string is built in reverse using `n % base` to calculate the value of the lowest digit:
(*Note: The below examples of code are not up-to-date, though they still give a general idea of how `to_string` works.*)
```cpp
constexpr to_string_t() {
auto ptr = buf + sizeof(buf) / sizeof(buf[0]);

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