JSON Mirror Compiler

0.4.12 verified Fri May 01 auth: no javascript

json-mirror-compiler is a TypeScript library (v0.4.12, pre-1.0, monthly releases) that compiles JSON Mirror specifications into executable code. It provides a compile function to transform JSON Pointer-based schema definitions into runtime implementations. Key differentiator: focuses on mirror patterns for bidirectional data mapping, unlike other JSON Pointer tools that only resolve paths. Ships TypeScript types.

Common errors

error Cannot find module 'json-mirror-compiler' ↓

cause Package not installed or mismatched version.

fix

Run npm install json-mirror-compiler@0.4.12 and ensure node_modules includes it.

error SyntaxError: The requested module 'json-mirror-compiler' does not provide an export named 'compile' ↓

cause Using a CommonJS require() which doesn't work with ESM-only packages.

fix

Change to import { compile } from 'json-mirror-compiler'.

error TypeError: compile is not a function ↓

cause Using the return value of compile incorrectly (expecting object instead of function) since v0.4.0.

fix

Ensure you call the compiled function: compile(spec)(input) or const fn = compile(spec); fn(input).

error Cannot read properties of undefined (reading 'jsonPointer') ↓

cause Passing an incomplete spec object without source or target fields.

fix

Make sure spec has both 'source' and 'target' objects with 'jsonPointer' strings.

Warnings

gotcha Package is pre-1.0 (v0.4.12); API may change without major version bump. ↓

fix Pin exact version in package.json and review changelog before updating.

gotcha Known breaking change in v0.4.0: Return type of compile changed from object to function. ↓

fix Update code to treat compile() output as a function rather than a static object.

gotcha ESM-only package; CommonJS require will throw an error. ↓

fix Use ES import syntax or switch to a dynamic import if in a CommonJS context.

gotcha TypeScript types shipped but may be incomplete in some versions. ↓

fix Check type definitions at node_modules/json-mirror-compiler/dist/index.d.ts; contribute fixes if needed.

Install

npm install json-mirror-compiler

yarn add json-mirror-compiler

pnpm add json-mirror-compiler

Imports

compile

wrong

const compile = require('json-mirror-compiler')

correct

import { compile } from 'json-mirror-compiler'

ESM-only package; no CommonJS support.

default export

wrong

const jsonMirrorCompiler = require('json-mirror-compiler')

correct

import jsonMirrorCompiler from 'json-mirror-compiler'

Default export is available but undocumented; named import is preferred.

MirrorSpec type

wrong

import { MirrorSpec } from 'json-mirror-compiler'

correct

import type { MirrorSpec } from 'json-mirror-compiler'

TypeScript type import recommended for type-only usage.

Quickstart

Demonstrates basic usage of the compile function with a simple mirror spec.

import { compile } from 'json-mirror-compiler';

const spec = {
  source: { jsonPointer: '/data' },
  target: { jsonPointer: '/mirrored' }
};

const compiledFn = compile(spec);
const result = compiledFn({ data: { value: 42 } });
console.log(JSON.stringify(result)); // {"mirrored":{"value":42}}