Email Generator for C++
Requires C++23 (e.g., -std=c++23 for GCC/Clang, /std:c++latest for MSVC).
API Reference · Usage Guide · Data and Method · Releases
Email addresses in each country's style, for tests, fixtures and generated users. The local part follows the country's naming habits from a given name, family name, nickname and birth year, and the domain is a provider people use there. A safe option uses the reserved example.* domains.
Features
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Locale-matched Local Parts. ana.souza, a.souza85, souza_ana, handles: nine style profiles weight the shapes by country. Names are folded to ASCII (Ørsted is orsted) and particles skipped (da Silva is silva).
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Provider Domains by Country. Global webmail plus the providers of the country (web.de, uol.com.br, qq.com, ...), by weight.
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Safe for Tests. safe gives example.com, example.net or example.org (RFC 2606), so a message sent to the address reaches nobody.
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Deterministic Seeding. Per-call get_email(request, seed) for reproducible results, and seed() on the result for replaying a previous generation with the same request and data.
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Batch Generation. Generate thousands of results from one seed, on several threads with the same output for any thread count, optionally unique by a key, and stream them as JSON Lines or CSV (see the usage guide).
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Identical Everywhere. A seed gives the same result on every compiler, standard library and CPU (GCC, Clang, MSVC, Emscripten; x86-64 and ARM64), checked by known-answer tests.
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Extensible Data. Load your own TSV layers on top of the shipped data to add, change or remove entries (extend()), checked before they are applied.
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JSON and Replay. to_json() on every result, and a signature() recording the seed and the data it came from.
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Compiled-in Data. Define DASMIG_EMAIL_EMBED to build the lite tier into the program, for WebAssembly and other builds without files.
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Multi-Instance Support. Construct independent emg instances with their own data and random engine.
Integration
emailgen.hpp is the library released here. Keep core.hpp and the core/ directory (dasmig-core) in the same directory. Add
#include <dasmig/emailgen.hpp>
to the files you want to use it in, and supply the resources folder (or define DASMIG_EMAIL_EMBED).
Usage
#include <dasmig/emailgen.hpp>
#include <iostream>
auto& gen = dasmig::emg::instance(); // loads the lite tier
// The names are plain values; the country sets the style and the domain.
auto e = gen.get_email({.country = "DE", .given = "Zoë", .family = "Müller", .birth_year = 1988});
std::cout << e << '\n'; // [email protected]
std::cout << e.kind << '\n'; // free
// No names: a handle in the country's style.
std::cout << gen.get_email({.country = "JP"}) << '\n';
// An address that reaches nobody, for tests.
std::cout << gen.get_email({.given = "Sam", .family = "Lee", .safe = true}) << '\n'; // [email protected]
// The same seed gives the same result everywhere.
auto again = gen.get_email({.country = "DE", .given = "Zoë", .family = "Müller", .birth_year = 1988}, e.seed());
See the usage guide for everything else.
Building
make # example
make test # tests
make bench # benchmarks, results in build/bench.tsv
make test-embed # tests with the lite tier compiled in
make coverage # code coverage
make lint # clang-tidy
make docs # API docs
make embed # regenerate dasmig/emailgen_data.hpp from resources/lite
Compiler Support
Tested with:
- Clang 18+ (
-std=c++23)
- GCC 14+ (
-std=c++23)
- MSVC 19.38+ (
/std:c++latest)
- Emscripten 3.1.74
Dependencies
| Dependency | Version | Bundled | Purpose |
|---|
| dasmig-core | 1.4 | Yes (core.hpp, core/) | Platform-independent random engine and distributions, data layers, JSON |
| Catch2 | 3.x | Yes (amalgamated) | Unit testing |
Related Libraries
License
This library is released under the MIT License.
MIT License
Copyright (c) 2026 Diego Dasso Migotto
