describers.md

Describers

Describers set restrictions on properties.

• Scalars
  • Nil
  • Bool
  • Int
  • Num
  • Str
• Map
  • MonoMap of Prop P
  • PolyMap
  • StructuredMap of struct V
• List
  • Array of Prop P with size N
  • MonoList of Prop P

Scalars

Nil

Mapped to std::nullptr_t

prop<Type::Nil>();

No restrictions available.

Bool

Mapped to bool

prop<Type::Bool>();

No restrictions available.

Int

Mapped to integer types such as int, long, unsigned int, etc.

prop<Type::Int>()
	.multipleOf(3)
	.interval(5 < x <= 42)
	.withClamp();

.multipleOf(...)

Value is restricted to multiples of the given value.

.interval(...)

Value is restricted to the given interval.

.withClamp(...)

Validation passes even if the value is not in the specified interval. Instead, when the value is accessed, it is clamped to fit the interval.

Num

Mapped to floating point types such as float, double, long double, etc.

prop<Type::Num>()
	.multipleOf(0.2)
	.interval(2.718 < x <= 3.14)
	.withClamp();

.multipleOf(...)

Value is restricted to multiples of the given value.

.interval(...)

Value is restricted to the given interval.

.withClamp(...)

Validation passes even if the value is not in the specified interval. Instead, when the value is accessed, it is clamped to fit the interval.

Str

Mapped to std::string.

prop<Type::Str>()
	.oneOf({"foo", "bar", "baz"})
	.length(2 < x <= 7);

.oneOf(...)

Value is restricted to one of the given values.

.length(...)

Length of the value is restricted to the given interval.

Map

MonoMap of Prop P

Mapped to std::unordered_map<std::string, P::StorageType>.

prop<Type::Map>()
	.of(
		prop<Type::Int>()
			.multipleOf(7)
	)
	.containing({"foo", "bar", "baz"});

// Shorthand
prop<Type::Map>().of<Type::Int>
	.containing({"foo", "bar", "baz"});

.containing(...)

Value is restricted to contain the given keys.

PolyMap

No type is mapped. Accessible only by Node.

Node node(...);
node["foo"].is<Type::Int>().interval(0 < x).withDefault(2);
node[req("bar")].is<Type::Str>().oneOf({"get", "set"});
node["baz"].is<Type::Map>().of<Type::Str>();

cray::req(...)

Value is restricted to contain the given key.

StructuredMap of struct V

Mapped to struct V.

struct V {
	int foo;
	std::optional<std::string> bar;
	std::vector<double> baz;
};

prop<Type::Map>().to<V>()
	| field("foo", &V::foo)
	| field("bar", &V::bar)
	| field("baz", &V::baz, prop<Num>().interval(0 < x));

cray::field(...)

Value is restricted to contain the given key with the given type. The key can be omitted if the given type is instance of std::optional.

List

Array of Prop P with size N

Mapped to std::array<P::StorageType, N>.

prop<Type::List>()
	.of<3>(
		prop<Type::Str>()
			.length(3 < x < 12)
	);

// Shorthand
prop<Type::List>().of<Type::Int, 3>();

No restrictions available.

MonoList of Prop P

Mapped to std::vector<P::StorageType>.

prop<Type::List>()
	.of(
		prop<Type::Str>()
			.oneOf({"foo", "bar", "baz"})
	)
	.size(x < 13);

// Shorthand
prop<Type::List>().of<Type::Int>()
	.size(x < 13);

.length(...)

Size of the value is restricted to the given interval.