ractive.subtract()

edit this page

Decrements the value of the given keypath.

ractive.subtract( keypath[, number ])

Returns a Promise (see Promises)

keypath String

The keypath of the number we're decrementing, e.g. count

number

Defaults to 1. The number to decrement by

Example

This is useful for numeric counters. Instead of using ractive.get() and ractive.set() in succession, using add() and subtract() will simplify your code.

quantityBox = new Ractive({
  template: [
    "<button on-click='decrease'> - </button>",
    "<span></span>",
    "<button on-click='increase'> + </button>",
  ].join(""),

  data: {
    quantity: 20
  }
});

quantityBox.on({
  decrease: function () { this.subtract(); },
  increase: function () { this.add(); }
  }
});