mp

A small, 0BSD-licensed metaprogramming library for C++17.

This is intended to be a lightweight and easy to understand implementation of a subset of useful metaprogramming utilities.

Usage

Just add the include directory to your include path. That's it.

typelist

A mp::list is a list of types. This set of headers provide metafunctions for manipulating lists of types.

Constructor

• mp::list: Constructs a list.
• mp::lift_sequence: Lifts a value sequence into a list. Intended for use on std::integral_sequence.

Element access

• mp::get: Gets a numbered element of a list.
• mp::head: Gets the first element of a list.
• mp::tail: Gets all-but-the-first-element as a list.

Properties

• mp::length: Gets the length of a list.
• mp::contains: Determines if this list contains a specified element.

Modifiers

• mp::append: Constructs a list with the provided elements appended to it.
• mp::prepend: Constructs a list with the provided elements prepended to it.

Operations

• mp::concat: Concantenates multiple lists together.
• mp::cartesian_product: Construct a list containing the cartesian product of the provided lists.

Conversions

• mp::lower_to_tuple: This operation only works on a list solely containing metavalues. Results in a std::tuple with equivalent values.

metavalue

A metavalue is a type of template std::integral_constant.

Constants

• mp::true_type: Aliases to std::true_type
• mp::false_type: Aliases to mp::false_type

Constructor

• mp::value: Aliases to std::integral_constant
• mp::bool_value: Aliases to std::bool_constant
• mp::size_value: Constructs a metavalue with value of type std::size_t
• mp::lift_value: Lifts a value of any arbitrary type to become a metavalue

Conversions

• mp::value_cast

Operations

• mp::value_equal: Compares value equality, ignores type. Use std::is_same for strict comparison.
• mp::logic_if: Like std::conditional but has a bool metavalue as first argument.
• mp::bit_not: Bitwise not
• mp::bit_and: Bitwise and
• mp::bit_or: Bitwise or
• mp::bit_xor: Bitwise xor
• mp::logic_not: Logical not
• mp::logic_and: Logical conjunction (no short circuiting, always results in a mp:bool_value)
• mp::logic_or: Logical disjunction (no short circuiting, always results in a mp:bool_value)
• mp::conjunction: Logical conjunction (with short circuiting, preserves type)
• mp::disjunction: Logical disjunction (with short circuiting, preserves type)
• mp::sum: Sum of values
• mp::product: Product of values

metafunction

• std::void_t: Always returns void.
• mp::identity: Identity metafunction. Can be used to establish a non-deduced context. See also C++20 std::type_identity.
• mp::apply: Invoke a provided metafunction with arguments specified in a list.
• mp::map: Apply a provided metafunction to each element of a list.
• mp::bind: Curry a metafunction. A macro MM_MP_BIND is provided to make this a little prettier.

traits

Type traits not in the standard library.

function_info

• mp::parameter_count_v: Number of parameters a function has
• mp::parameter_list: Get a typelist of the parameter types
• mp::get_parameter: Get the type of a parameter by index
• mp::equivalent_function_type: Get an equivalent function type (for MFPs this does not include the class)
• mp::equivalent_function_type_with_class: Get an equivalent function type with explicit this argument (MFPs only)
• mp::return_type: Return type of the function
• mp::class_type: Only valid for member function pointer types. Gets the class the member function is associated with.

integer_of_size

• mp::signed_integer_of_size: Gets a signed integer of the specified bit-size (if it exists)
• mp::unsigned_integer_of_size: Gets an unsigned integer of the specified bit-size (if it exists)

Misc

• mp::is_instance_of_template: Checks if a type is an instance of a template class.

License

Please see LICENSE-0BSD.