stac

stac

Maintain a sorted stack of things.

Examples

Add arbitrary things to a stack

var createStac = require('stac')
  , stack = createStac();

stack.add('A');
stack.add(23);
stack.add(['foo', 'bar']);

stack.first({my: 'Object'});
stack.last('The End');

console.log(stack.items());
// [ { my: 'Object' }, 'A', 23, [ 'foo', 'bar' ], 'The End']

Add things to a stack with weights

var createStac = require('stac')
  , stack = createStac();

stack.add(3, 'C');
stack.add(1, 'A');
stack.add(4, 'D');
stack.add(2, 'B');

stack.forEach(function (letter) {
  console.log(letter);
});
// A
// B
// C
// D

Advanced usage: custom sortBy and comparator

var createStac = require('stac')
var stack = createStac({
  sortBy: function (item) {
    return item.width * item.height;
  },
  comparator: function (a, b) {
    if (a === b) return 0;
    // Reverse sort
    return a < b ? 1 : -1;
  }
});

stack.add({color: 'red', width: 5, height: 4});
stack.add({color: 'green', width: 1, height: 2});
stack.add({color: 'blue', width: 8, height: 2});

console.log(stack.map(function (item) {
  return item.color;
}));
// [ 'red', 'blue', 'green' ]

API

createStac([options])

The only export for this module. Returns instances of Stac objects.

var createStac = require('stac');

// Create a stac object.
var stack = createStac();

// Create a stac object with options.
var another = createStac({
  sortBy: 'age'
});

options

• sortBy - String or function. If string, and items are objects, then the value of the property at this key will be used for sorting. If function, then the function will be called with the item to determine its sort value. Default: 'weight'.
• defaultVal - If no sorting value is provided or can be determined for an item, then this value will be used. Default: 0.
• comparator - A custom comparator function (a, b). Will be called with the values of two items to compare. Should return 0, 1, or -1; similar to how Array.prototype.sort() is used. Default: (sort by numeric value).

Methods

Methods of Stac objects.

add ( [val], item )

Add an item to the stack. Optionally pass a value to sort by.

remove ( item )

Remove an item from the stack.

first ( [val], item ) | unshift ( [val], item )

Add an item to the front of the stack. Items inserted this way will always be sorted in front of items added with add() or last(). Within the first set, items will be sorted normally.

last ( [val], item ) | push ( [val], item )

Add an item to the end of the stack. Items inserted this way will always be sorted behind items added with add() or first(). Within the last set, items will be sorted normally.

multi (method, items)

Helper to operate on multiple items with one call. Example: stack.multi('add', ['A', 'B', 'C']).

clone()

Returns a copy of a stack.

Note: items in the stack will still reference the originals.

items() | toJSON()

Returns the sorted array of items in the stack.

forEach ( iterator, [thisArg] )

Iterate over items in the stack (just like Array.prototype.forEach).

map ( func, [thisArg] )

Returns a mapped representation of the stack (just like an Array.prototype.map).

pop()

Returns and removes the last item from the stack (similar to Array.prototype.pop).

shift()

Returns and removes the first item from the stack (similar to Array.prototype.shift).

Properties

Properties of Stac objects.

length

Returns the current length of the stack.

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Developed by Terra Eclipse

Terra Eclipse, Inc. is a nationally recognized political technology and strategy firm located in Aptos, CA and Washington, D.C.

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License: MIT

Copyright (C) 2012 Terra Eclipse, Inc. (http://www.terraeclipse.com)

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.