Calculation Instance Factory

The Calculation Instance Factory lets you register a custom JavaScript calculation service that Eaze formulas can call as this.<name>.<method>(...). Use it when standard Eaze isn't enough: stateful calculations, cross-spreadsheet data not loaded into the Workbook, or math backed by an external library.

Configuration

Add a <ComputeInstanceFactory> block to the spreadsheet designer XML:

<ComputeInstanceFactory>
  <Instance Name="my.calculator" FactoryFunction="myLib.createCalculator">
    <FactoryFunctionArguments>
      <SqlScript Id="@Object[someSqlScript].Id" />
    </FactoryFunctionArguments>
  </Instance>
</ComputeInstanceFactory>

Attribute	Description
`Instance/@Name`	Path on `this` your formulas use — e.g. `this.my.calculator`
`Instance/@FactoryFunction`	A function on the global `window` object that returns the service instance
`FactoryFunctionArguments/SqlScript`	SQL Scripts whose result sets are passed as positional arguments to the factory function (currently only data-returning scripts are supported)

Using the service in formulas

@Total[] = this.my.calculator.add(@P01[], @P02[]);

When to reach for it

Cross-spreadsheet data that is not loaded into the Workbook
Conditional logic too complex for Eaze
Math functions outside the Eaze standard library
Stateful calculations that span multiple cell changes
One shared calc service per spreadsheet

Implementation options

Option 1 — JavaScript Solution Object for small, self-contained services.

Option 2 — External build (TypeScript / Node / Jasmine etc.) deployed to /Scripts/plugins. Declare load order in /Scripts/plugins/plugins.json:

{ "files": ["3rdparty-lib1.js", "3rdparty-lib2.js", "mycalc-lib.js"] }

Lighter-weight alternative (2025.5+)