About:Scripting in Memento

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« Page as of 2021-11-19, editions Mobile 4.10.3, Desktop 1.10.3 »

Native Memento Calculation scripting

The specifications for scripting for the Calculation field type is described in Calculation field.

Scripting Memento in JavaScript

Scripting in JavaScript is available in JavaScript field, Triggers, Actions, and Custom Data Sources.

The JavaScript field type

Like the Memento Calculation field type that came before it, the JavaScript field exists to produce ("return") a value calculated with an expression or formula. JavaScript fields use a somewhat simplified form of Memento JavaScript. For instance, it assumes the current entry for its context, while in full Memento JavaScript, the script must locate & provide the entry to operate on. While it can access any field in any library the current library is linked to, it doesn't have the complexity to access any field in any entry in any library, as you can in full Memento JavaScript. See Write scripts in JavaScript for Memento#JavaScript field for a detailed discussing of the JavaScript field.

Example JavaScript field usage

  • The field() function gets the value of the field from Memento.
  • Anything after "//" is ignored, so you can use it for comments.
  • For numbers, x * y means the numerical product of x times y.
  • x = y means for Memento to assign to x the value of y.
  • For numbers, x + y means the sum of x and y, while if x & y are strings of text, it means x concatenated with y.
Item price    // on an invoice
field("Unit price") * field("Quantity")
Amount for display    // Final sum
field("Total") + " widgets"
Limited    // The capped amount
value = field("Value"); if (value <= StandardLimit) value else StandardLimit

moment.min.js — a possibly useful wrapper for JavaScript dates & times

See http://momentjs.com and its subordinate pages Guides and Docs.

To get the current date, use moment().toDate(). To get the current date & time, use moment().toDate().getTime().