wildling

C++ library and CLI for pattern-based string generation. Zero third-party dependencies (C++17 standard library only). Includes a minimal JSON parser for --template.

Docs: Website · Sandbox · Syntax · Source

Registry: GitHub Releases

Example

http://${'dev,stage,prod'}\-${'api,web'}#{0-2}.example.${'com,net,org'}/@.html

(The \- is a literal hyphen; bare - would mean “one letter or digit”. @ is one lowercase letter.)

That builds URL-shaped candidates: scheme http://, then environment × service × optional digits × TLD, then a one-letter path page. Three environments, two services, zero–two digits ('', 0–9, 00–99), three TLDs, and a–z → 51948 strings — the kind of list you generate for fuzzing links or probing staging hosts, not type out.

A few of them:

http://dev-api.example.com/a.html / http://stage-web.example.com/z.html
http://dev-api0.example.net/a.html / http://prod-web9.example.org/m.html
http://dev-api00.example.com/a.html / http://prod-web99.example.org/z.html

Named dictionaries (%{'hosts'}) work the same way when the word lists live in files.

Try it in the sandbox, or see pattern syntax for length ranges, dictionaries, and escapes.

Install

From this repository:

cd cpp
./build.sh
./bin/wildling "Year 19##"

From a release tag:

git clone --branch v2.0.7 --depth 1 https://github.com/dotmonk/wildling.git
cd wildling
./build.sh cpp

GitHub Release assets (Linux x86_64 CLI + source tarballs) are attached to each vX.Y.Z release.

CMake (library + CLI), including FetchContent from the monorepo:

include(FetchContent)
FetchContent_Declare(
  wildling
  GIT_REPOSITORY https://github.com/dotmonk/wildling.git
  GIT_TAG v2.0.7
  SOURCE_SUBDIR cpp
)
FetchContent_MakeAvailable(wildling)
target_link_libraries(myapp PRIVATE wildling)

Produces dist/wildling. Link against the sources under src/ (except cli.cpp) to use as a library:

#include "wildling.hpp"

wildling::Dictionaries dictionaries;
wildling::Wildling w({"Year 19##"}, dictionaries);
auto value = w.next();
while (value.has_value()) {
    std::cout << *value << '\n';
    value = w.next();
}

CLI

./bin/wildling "Year 19##"
./bin/wildling --dictionary planets:../dictionaries/planets.txt "%{'planets'}"
./bin/wildling --template ./config.json

Help text and --check output follow docs/cli.md / docs/help.txt.

Build

./build.sh   # Docker (gcc:14-bookworm): g++ -std=c++17 → dist/wildling

Project tests live in ../tests/ and are run with ../test.sh.