The stable release documentation can be found here https://pavlovich.github.io/safe.accessors/

safe.accessors

Javascript lacks a way to safely get and set values of nested attributes or a way to call functions with value retrieved from a nested structure. This is an attempt to fill that gap.

Usage

In Node.js and Browserify

Install from npm

npm install safe.accessors

Require individual functions

var safeGet = require("safe.accessors/safeGet");

safeGet(myObj, "x.y.z.a.b.c", default, allowNull);
// => xxx

or load the full library to enable chaining

var sa = require("safe.accessors");

sa(x).trim().capitalize().value();
// => "xxx"

but especially when using with Browserify the individual function approach is recommended because using it you only add those functions to your bundle you use.

In Meteor

From your Meteor project folder

    meteor add safe.accessors:safe.accessors

and you'll be able to access the library with the sa global from both the server and the client.

var allowNulls = false;
sa.safeGet(obj, 'a.b.c.d.e', 'default value', allowNulls);
// => default value

s("   epeli  ").trim().capitalize().value();
// => "Epeli"

Others

The dist/underscore.string.js file is an UMD build. You can load it using an AMD loader such as RequireJS or just stick it to a web page and access the library from the s global.

Underscore.js/Lo-Dash integration

It is possible use as Underscore.js/Lo-Dash extension

_.mixin(sa.exports());

Download

• Development version Uncompressed with Comments
• Production version Minified

API

Individual functions

safeGet(object, [ path='', defaultValue=null, allowNulls=false]) => object

Traverses the supplied chain of attributes of the provided object until it reaches the target (final) attribute or hits a 'null'. If it successfully reaches the end, the value of the final attribute is returned. If a null is encountered or if the final value is null, then, if nulls are allowed, a null is returned. Otherwise, the default value is returned.

safeGet({something: {somethingElse: {theFinalAttribute: 'hello'}, 'something.somethingElse.theFinalAttribute', 'default value', false);
// => "hello"

safeGet({something: {somethingElse: {theFinalAttribute: 'hello'}, 'something.somethingElseXX.theFinalAttributeXXX', 'default value');
// => "default value"

safeGet({something: {somethingElse: {theFinalAttribute: null}, 'something.somethingElse.theFinalAttribute', 'default value', true);
// => null

safeSet(object, [ path='' ]) => object

Sets the value of the given path relative to the supplied object to the provided value.

safeSet({}, "a.b.c.d", 'hello');
// => 'hello'

safeSet({a: {b: {c: {d: 'yes'}}}}, "a.b.c.d", 'hello');
// => 'hello'

safeSet({a: {b: {c: {d: 'yes'}}}}, "a.b.c.d", 'hello', false);
// => 'yes'

safeCall(object, [path='', defaultValue, functionToCall, context, allowNull, allowUndefined, defaultReturn, allowNullResult, allowUndefinedResult]) => string

Converts first letter of the string to uppercase. If true is passed as second argument the rest of the string will be converted to lower case.

safeCall("foo Bar");
// => "Foo Bar"

safeCall("FOO Bar", true);
// => "Foo bar"

isVoid(object) => boolean

Returns true if the supplied object is undefined or null, false otherwise.

isVoid("hello");
// => false

isVoid(null);
// => true

isVoid(undefined);
// => true

Maintainers

This library is maintained by

• Peter Pavlovich – @pavlovich

Licence

The MIT License

Copyright (c) 2015 Peter Pavlovich [email protected]

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.