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Literal operators in xtd

Namespace: xtd::literals
Library: xtd.core (with extensions from other modules)

Overview​

The xtd::literals namespace provides user-defined literal operators that simplify the creation of commonly used xtd types.

These literals improve readability and consistency in code, allowing developers to express values in a concise and natural way.

Design Principle​

All literals are defined under the xtd::literals namespace, even if the related types belong to other namespaces such as xtd::drawing or xtd::net.

This allows a unified using directive:

using namespace xtd::literals;

Without the need to import module-specific namespaces like xtd::net::literals or xtd::drawing::literals.

Organization​

Even though the operators are grouped under xtd::literals, their implementations follow a modular layout that respects the logical ownership of types:

xtd.core
├── xtd
│   └── literals
│       ├── byte.hpp
│       ├── char32.hpp
│       ├── version.hpp
│       └── ...

xtd.drawing
├── xtd
│   └── literals
│       └── color.hpp

xtd.net
├── xtd
│   └── literals
│       └── ip.hpp

Each header only includes what it needs and keeps responsibility localized.

Available Literal Operators​

LiteralTarget TypeExample
_b, _s8xtd::byte42_b or "255"_b
_cxtd::char32'A'_c
_sxtd::ustring or time_span"text"_s or 1.5_s
_h, _m, _ms, _us, _ns, _dxtd::time_span1_h, 500_ms, etc.
_versxtd::version"1.2.3"_vers
_colorxtd::drawing::color"dodger blue"_color or "FF0000"_color
_countryxtd::forms::country"Belgium"_country or "BE"_country or "BEL"_country
_ipxtd::net::ip_address"127.0.0.1"_ip or "::1"_ip

The following literal operators page shows all xtd literal operators.

Safety and Error Handling​

All string-based literal operators use their respective parse methods internally:

"1.2.3"_vers → version::parse("1.2.3")
"FF0000"_color → color::parse("FF0000")

Exceptions such as xtd::format_exception or xtd::argument_exception will be thrown if parsing fails.

Example​

#include <xtd/xtd>

using namespace xtd::literals;

auto main() -> int {
  auto version = "1.2.3"_vers;
  auto color = "dodger blue"_color;
  auto ip = "192.168.1.1"_ip;
  auto delay = 2.5_s;

  console::write_line("version: {}", version);
  console::write_line("color: {}", color);
  console::write_line("ip: {}", ip);
  console::write_line("delay: {}", delay.total_milliseconds());
}

Notes​

  • All literals are optional. If you don’t include the xtd::literals namespace, you can still construct the values manually.
  • You are free to include only the headers you need:
    #include <xtd/literals/version.hpp>
    #include <xtd/literals/color.hpp>

See also

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