@mettascript/libraries

The PeTTa standard libraries as importable MeTTa modules. The package registers module source strings with the core builtin-module registry, so a program can use import! to load vector, roman, combinatorics, patrick, datastructures, spaces, nars, or pln.

npm install @mettascript/libraries

@mettascript/node, @mettascript/hyperon, and @mettascript/browser register these libraries for you. If you use bare @mettascript/core, import this package or call registerLibraries() before evaluating source that imports one of the modules.

API

function registerLibraries(): void;
const LIBRARY_MODULE_SRCS: Readonly<Record<string, string>>;

registerLibraries adds each library source to the core builtin-module registry. It is safe to call more than once. LIBRARY_MODULE_SRCS is the generated map of module name to MeTTa source.

The package registers itself as a side effect when imported:

import "@mettascript/libraries";

You can also call the function explicitly:

import { registerLibraries } from "@mettascript/libraries";

registerLibraries();

Libraries

module	contains
vector	dot product, norm, cosine similarity, and random unit vectors
roman	maps, folds, set operations, composition, pair accessors, and list-end helpers
combinatorics	ranges, unordered pairs, k-combinations, and list prefixes
patrick	compose, which applies a list of single-argument functions right to left
datastructures	a functional queue and a unique-insert helper for spaces
spaces	atomspace migration and removal helpers
nars	NARS truth functions, inference rules, and bounded forward querying
pln	PLN truth functions, inference rules, and bounded forward querying

See Standard libraries for worked MeTTa examples for each module.

Example

import { format, runProgram } from "@mettascript/core";
import { registerLibraries } from "@mettascript/libraries";

registerLibraries();

const [importResult, dotResult] = runProgram(`
  !(import! &self vector)
  !(dot (1.0 2.0 3.0) (4.0 5.0 6.0))
`);

console.log(importResult.results.map(format)); // ["()"]
console.log(dotResult.results.map(format)); // ["32.0"]

Library imports are still explicit at the MeTTa level. Registering the package makes the named modules available, but a program only loads a module into &self when it evaluates import!.