Bullean NPM | npm.io

bullean

boolean expression interpreter

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This is based on the rancher catalog app show_if question variable. You can read more about it at the link below.

https://rancher.com/docs/rancher/v2.x/en/helm-charts/legacy-catalogs/creating-apps/#question-variable-reference

Features

parentheses support
support for order of operations

Installation

npm install --save bullean

Dependencies

NodeJS

Usage

import Bullean from 'bullean';

const bullean = new Bullean({
  hello: 'world',
  howdy: 'texas'
});
console.log(bullean.eval('hello=world||howdy=world')); // true
console.log(bullean.eval('hello=world&&howdy=world')); // false

import Bullean from 'bullean';

const bullean = new Bullean();
const ast = bullean.parse('hello=world&&howdy=texas');
console.log(JSON.stringify(ast, null, 2));

This will output the following AST.

{
  "operator": "and",
  "predicates": [
    {
      "operator": "=",
      "left": {
        "name": "hello",
        "type": "identifier"
      },
      "value": "world"
    },
    {
      "operator": "=",
      "left": {
        "name": "howdy",
        "type": "identifier"
      },
      "value": "texas"
    }
  ]
}

You can find more examples in the tests at the link below.

src/bullean.spec.ts