Glaze provides a number of wrappers that indicate at compile time how a value should be read and/or written. These wrappers allow you to modify the read/write behavior of a type without affecting your C++ class.
Example:
Say we have the following class, but we want to read and write the number as a JSON string.
struct foo {
int x = 5;
};We use a wrapper in our glz::meta to indicate this string handling.
template <>
struct glz::meta<foo> {
using T = foo;
static constexpr auto value = object("x", quoted_num<&T::x>);
};Now our input and output for foo will look like:
{ "x": "5" }Because wrappers are known at compile time it means this behavior can be highly optimized and does not add much overhead to the default behavior in Glaze.
glz::quoted_num<&T::x> // reads a number as a string and writes it as a string
glz::quoted<&T::x> // reads a value as a string and unescapes, to avoid the user having to parse twice
glz::number<&T::x> // reads a string as a number and writes the string as a number
glz::invoke<&T::func> // invokes a std::function or member function with n-arguments as an array input
glz::custom<&T::read, &T::write> // calls custom read and write std::functions or member functions
glz::manage<&T::x, &T::read_x, &T::write_x> // calls read_x() after reading x and calls write_x() before writing x
glz::raw<&T::x> // write out string like types without quotes
glz::raw_string<&T::string> // do not decode/encode escaped characters for strings (improves read/write performance)