listtype.js

Infers type from an arbitrary list of strings. Useful to build filters and other form components from user data.

Use it to determine if strings/numbers from a list have a common type. Possible return values are:

• natural: all natural numbers (> 0)
• integer: integers (has at least one number < 0)
• float: all floats (has at least one float)
• enum: each string is from a limited list of values
• flag: only one value
• string: finally, just a list of arbitrary strings (either all strings, or more than one type)

By default, null and 'empty string' are excluded from all checks.

Warning! This library does not attempt to sanitize data.

Install

$ npm install listtype.js

Usage

// import
var listtypejs = require('listtype.js')
   
var type = listtypejs(['3', 2, 5, '-4']); // type = integer
var type = listtypejs(['fruit', 'fruit', 'vegetable', 'fruit']); // type = enum

See tests in test/ for a comprehensive list of examples.

Contributing

Fork and PR.

Tests are done with mocha. Please make sure all tests pass:

npm run test

License

MIT