moai-lang-cpp

name	moai-lang-cpp
description	Modern C++ (C++23/C++20) development specialist covering RAII, smart pointers, concepts, ranges, modules, and CMake. Use when developing high-performance applications, games, system software, or embedded systems.
license	Apache-2.0
compatibility	Designed for Claude Code
allowed-tools	Read Grep Glob Bash(g++:*) Bash(gcc:*) Bash(clang:*) Bash(clang++:*) Bash(cmake:*) Bash(make:*) Bash(ctest:*) Bash(valgrind:*) Bash(gdb:*) mcp__context7__resolve-library-id mcp__context7__get-library-docs
user-invocable	false
metadata	{"version":"1.1.0","category":"language","status":"active","updated":"2026-01-11","modularized":"true","tags":"language, cpp, c++23, c++20, cmake, raii, smart-pointers, concepts"}
progressive_disclosure	{"enabled":true,"level1_tokens":100,"level2_tokens":5000}
triggers	{"keywords":["C++","cpp","CMake","RAII","smart pointer","concept","range",".cpp",".hpp","CMakeLists.txt","vcpkg","conan"],"languages":["cpp","c++"]}

Quick Reference (30 seconds)

Modern C++ (C++23/C++20) Development Specialist - RAII, smart pointers, concepts, ranges, modules, and CMake.

Auto-Triggers: .cpp, .hpp, .h, CMakeLists.txt, vcpkg.json, conanfile.txt, modern C++ discussions

Core Capabilities:

• C++23 Features: std::expected, std::print, std::generator, deducing this
• C++20 Features: Concepts, Ranges, Modules, Coroutines, std::format
• Memory Safety: RAII, Rule of 5, smart pointers (unique_ptr, shared_ptr, weak_ptr)
• STL: Containers, Algorithms, Iterators, std::span, std::string_view
• Build Systems: CMake 3.28+, FetchContent, presets
• Concurrency: std::thread, std::jthread, std::async, atomics, std::latch/barrier
• Testing: Google Test, Catch2
• Package Management: vcpkg, Conan 2.0

Quick Patterns

Smart Pointer Factory Pattern: Create a class with a static factory method that returns std::unique_ptr. Include a header for memory, define a Widget class with a static create method taking an int value parameter. The create method uses std::make_unique to instantiate and return the Widget. The constructor should be explicit and take the value parameter, storing it in a private member variable.

Concepts Constraint Pattern: Define a concept named Numeric that combines std::integral or std::floating_point constraints. Create a template function square that requires T to satisfy the Numeric concept, taking a value parameter and returning value multiplied by itself.

Ranges Pipeline Pattern: Use std::views::iota to create a range from 1 to 100, pipe it through a filter to select even numbers, then transform by squaring each value, and finally take the first 10 results.

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Implementation Guide (5 minutes)

C++23 New Features

std::expected for Error Handling: Create an enum class ParseError with InvalidFormat and OutOfRange values. Define a parse_int function that takes std::string_view and returns std::expected containing either int or ParseError. Inside, use a try-catch block to call std::stoi. Catch std::invalid_argument and return std::unexpected with InvalidFormat, catch std::out_of_range and return std::unexpected with OutOfRange. On success, return the parsed value directly. Usage involves checking the result with if(result) and accessing the value with asterisk operator or handling the error case.

std::print for Type-Safe Output: Include the print header and use std::println for formatted output with curly brace placeholders. Supports format specifiers like colon followed by hash x for hexadecimal or colon followed by .2f for floating point precision.

Deducing This (Explicit Object Parameter): Define a Builder class with a data_ member string. Create a template method append with template parameter Self that takes this Self and and a string_view parameter. Forward self with std::forward and return Self and and. This enables chaining on both lvalue and rvalue objects.