node-value-filter

Providing convenient methods to do fitering to the variables.

Install

node install node-value-filter

Usage

const filter = require('node-value-filter');

var a = '"123.456"';
var b = filter(a).trim('"').number().int().get();
// b = 123;

Built-in filters

.string(default)

• undefined => default | ''
• null => default | ''
• true => 'true'
• false => 'false'
• number => number.toString()
• object => object.toString()
• string => not changed

Parameters:

• default string (optional)

Example:

var a = filter(123.456).string().get();
// a = '123.456' (string)
var b  = filter(null).string('-').get();
// b = '-' (string)

.trim()

• string => string.trim()
• others => not changed

Example:

var a = filter([' abcdef ']).string().trim().get();
// a = 'abcdef' (string)

.trim(chars)

• string => string.replace( /^chars|chars$/gm, '' )
• others => not changed

Parameters:

• chars string | RegExp

Example:

var a = filter('"abcdef"').trim('"').get();
// a = abcdef (string)
var b = filter('{abcdef}').trim(/^{|}$/gm).get();
// b = abcdef (string)

.trim(prefix, suffix)

• string => string.replace( /^prefix|suffix$/gm, '' )
• others => not changed

Parameters:

• prefix string
• suffix string

Example:

var a = filter('{abcdef}').trim('{','}').get();
// a = abcdef (string)

.number(default)

• undefined => default | 0
• null => default | 0
• true => 1
• false => 0
• string => new Number( string ).valueOf() | default | 0
• object => new Number( object.toString() ).valueOf() | default | 0
• number => not changed

Parameters:

• default number (optional)

Example:

var a = filter('0xff').number().get();
// a = 255 (number)
var b = filter('abc').number(-1).get();
// b = -1 (number)

.int(radix, default)

• undefined => default | 0
• null => default | 0
• true => 1
• false => 0
• string => parseInt( string, radix | 10 ) | 0
• object => parseInt( object.toString(), radix | 10 ) | 0
• number => Math.trunc( number )

Parameters:

• radix integer (optional)
• default integer (optional)

Example:

var a = filter([123.456]).string().int().get();
// a = 123 (number)
var b = filter(['ff']).string().int(16).get();
// b = 255 (number)
var c = filter([]).string().int(-1).get();
// c = -1 (number)

.float(default)

• undefined => default | 0
• null => default | 0
• true => 1
• false => 0
• string => parseFloat( string ) | default | 0
• object => parseFloat( object.toString() ) | default | 0
• number => not changed

Parameters:

• default number

Example:

var a = filter(['1e2']).string().float().get();
// a = 100 (number)
var b = filter([]).string().float(0.1).get();
// b = 0.1 (number)

Custom filter

.custom(f, context)

Parameters:

• f function
• context object (optional)

Example:

var a = filter(something).custom((input)=>{
  // Do something with input
  return result;
}).get();

.bind(name, f, context)

Paramters:

• name string
• f function
• context object (optional)

Exampel:

filter
.bind('custom_name', (input, parameters...)=>{
  // Do something with input, parameters...
  return result;
})
.bind('other_name', ...);

var a = filter.custom_name(parameters...).get();
var b = filter.other_name(...).get();

Bugs or feature requests

Please contact to email

(Please add the prefix "[node-value-filter]" into the email title. Thanks!)

License

ISC