pascal

wildling

Free Pascal library and CLI for pattern-based string generation. Zero third-party units — FPC RTL only (System, SysUtils) with a hand-rolled JSON parser for --template. Pattern splitting is hand-rolled (no RegExpr).

Docs: Website · Sandbox · Syntax · Source

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 pascal
./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 pascal

Produces dist/wildling. Use the units under src/ (except cli.pas) as a library.

uses WildlingLib, ParsePattern;

var
  W: TWildling;
  Value: string;
begin
  W := CreateWildling(['Year 19##']);
  try
    while W.Next(Value) do
      WriteLn(Value);
  finally
    W.Free;
  end;
end.

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. Out-of-range --select / --range write out of range: <index> on stderr and exit 1.

Build

./build.sh   # Docker (gcc:14-bookworm + fpc): → dist/wildling + help.txt

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

Layout

pascal/
  src/
    token.pas         token expansion
    parsepattern.pas  hand-rolled pattern split + tokenizers
    generator.pas     single-pattern generator
    wildlinglib.pas   multi-pattern API
    json.pas          template JSON parser
    cli.pas           CLI entry point
  bin/wildling        launcher script
  build.sh            Docker build (fpc via apt)
  dist/               build output (gitignored)
  obj/                compiler units (gitignored)