Module resource

Resource identifiers and HTTP utilities.

Provides types and functions for resource identifiers (URI/IRI), namespace factories, HTTP error handling, and fetch operations.

Type Guards

import { isURI, isIRI } from "@metreeca/core";

const value = "http://example.org/resource";

if (isURI(value)) {
  // value is typed as URI (ASCII-only)
}

if (isIRI(value)) {
  // value is typed as IRI (allows Unicode)
}
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Identifier Factories

import { asURI, asIRI } from "@metreeca/core";

// Absolute identifiers

const absoluteURI = asURI("http://example.org/resource");
const absoluteIRI = asIRI("http://example.org/resource");

// Relative references

const relativeURI = asURI("../resource", "relative");
const relativeIRI = asIRI("../resource", "relative");

// Root-relative (internal) paths

const internalURI = asURI("/resource", "internal");
const internalIRI = asIRI("/resource", "internal");

// Unicode in IRIs (throws for URIs)

const unicodeIRI = asIRI("http://example.org/资源");
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Reference Operations

import { resolve, relativize, internalize, asURI } from "@metreeca/core";

const base = asURI("http://example.com/a/b/c");

// Resolve relative references against base

resolve(base, asURI("../d", "relative"));  // "http://example.com/a/d"
resolve(base, asURI("/d", "internal"));    // "http://example.com/d"

// Convert absolute to root-relative (internal) path

internalize(base, asURI("http://example.com/x/y"));  // "/x/y"

// Convert absolute to relative path

relativize(base, asURI("http://example.com/a/d"));   // "../d"
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Namespace Factories

import { createNamespace } from "@metreeca/core";

// Closed namespace with predefined terms

const rdfs = createNamespace("http://www.w3.org/2000/01/rdf-schema#", [
  "label",
  "comment"
]);

rdfs();           // IRI: "http://www.w3.org/2000/01/rdf-schema#"
rdfs.label;        // IRI: "http://www.w3.org/2000/01/rdf-schema#label"
rdfs("comment");   // IRI: "http://www.w3.org/2000/01/rdf-schema#comment"
rdfs("seeAlso");   // Throws RangeError: unknown term

// Open namespace for dynamic terms

const ex = createNamespace("http://example.org/");

ex();              // IRI: "http://example.org/"
ex("anything");    // IRI: "http://example.org/anything"
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HTTP Error Handling

import { Problem } from "@metreeca/core";

const problem: Problem = {
  status: 404,
  title: "Not Found",
  detail: "Resource /api/users/123 does not exist",
  instance: "/api/users/123",
  report: { timestamp: "2025-12-02T10:30:00Z" }
};
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Fetch Utilities

import { createFetch } from "@metreeca/core";

const guard = createFetch(fetch);

try {
  const response = await guard("https://api.example.com/data");
  // response.ok is guaranteed true
} catch (problem) {
  // problem is a Problem with parsed error details
  console.error(problem.status, problem.detail, problem.report);
}
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