evented attributes with automatic dependencies

Create a new attr with value set to val

attr = require('attr')

name = attr('Homer Simpson')

Read a value

name() // => 'Homer Simpson'

Write a value

name('Bart Simpson')

name() // => 'Bart Simpson'

• Emits "change" event with (value, previousValue).

name.on('change', function(new_name, old_name) {
  console.log('my name changed from', old_name, 'to', new_name)
})

Has the same API, except function is passed in and is run to determine the initial value. (has no setter)

fullName = attr(function() {
  return firstName() + ' ' + surName()
})

fullName() // => 'Homer Simpson'

fullName.dependencies // => [ firstName, surName ]

Dependencies on other simple (non-computed) are automatically calculated unless set explicitly via a second argument as in:

fullName = attr(function() {
  return firstName() + ' ' + surName()
}, [firstName])

fullName.dependencies // => [ firstName ]

Flips truthy to false and falsey to true

Increments value by 1 or val

Binds fn to the change event

force a change event

contains the current value. Use to get value without running the getter (most useful for computed attr)

contains the last value

Contains a list of dependencies (this will be null for simple attr)

By default function values are assumed to be computed. This behaviour can be turned off by setting autocompute.

Explicitly creates a computed attr - this is only useful if autocompute is turned off

Calculates a list of the simple (non-computed) attributes called by running this function

make && open test/index.html

MIT