What & why

string-interpolation-parser takes a map of parameters and a context object, and returns the same map with every {{ token }} placeholder replaced by the matching value from the context.

It is deliberately small: one function, no runtime dependencies, and the same behaviour in the browser and in Node.

At a glance

import parser from 'string-interpolation-parser';

const params = {
  welcome: 'Welcome, {{ vendor.name }}',
  order: 'Hi {{ customer }}, shipping to {{ store.data.name }}',
  total: 10,
  ignored: true, // dropped — not a string or number
};

const context = {
  vendor: { name: 'Felippe Maurício' },
  store: { data: { name: 'Rio de Janeiro' } },
  customer: 'Luciana Cabral',
};

parser(params, context);
// {
//   welcome: 'Welcome, Felippe Maurício',
//   order: 'Hi Luciana Cabral, shipping to Rio de Janeiro',
//   total: 10,
// }

The rules

• Only string and number values are kept. Anything else (booleans, null, undefined, arrays, objects) is dropped from the result.
• Numbers pass through untouched. Only string values are interpolated.
• Tokens are {{ ... }}. Whitespace inside the braces is ignored, so {{ user }} and {{user}} are equivalent.
• Paths can be dotted and indexed. {{ user.posts[0].title }} walks objects and arrays alike.
• Missing or falsy lookups become an empty string. No errors are thrown for absent keys.

Opt-in extras — fallbacks, filters, escaping, passthrough and raw — are covered in Features; the defaults above never change.

Try it live in the playground, or read the full API reference.