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FILEMAKER PRO HELP 842

The following example shows how to pass named parameters, while keeping the ability to check the

syntax of the second parameter of the

Let function (the example returns 6, 12):

ScriptParameter = "a = 5; b = 10"

Let( [a = Evaluate("Let( [" & Get(ScriptParameter) & "]; a )"),

b = Evaluate("Let( [" & Get(ScriptParameter) & "]; b )")]; a + 1

& ", " & b + 2 )

Note The Evaluate function evaluates an expression, including field values to be evaluated as a

calculation formula. It also allows you to specify field dependencies so that a calculation using the

evaluation function can be triggered due to changes in other fields of the same record. This function

evaluates user-defined formulas. For example, you can create a formula in the Total field that

computes state tax:

Evaluate(StateTaxFormula) + ShippingCost

where the StateTaxFormula field contains:

SubTotal * 1.0875

and the SubTotal field contains the subtotal before tax and shipping.

The Evaluate function has an optional second parameter, which is a field the calculation is

dependent on. When the dependent field contents change, FileMaker

Pro re-evaluates the

calculation. In the following example, the Total calculation will be re-evaluated when SubTotal

changes:

Evaluate(StateTaxFormula; SubTotal) + ShippingCost

The dependent parameter can also be useful in other cases. For example,

Evaluate(“Get(CurrentTimeStamp)”; [FieldB; FieldC])

will store a timestamp in the calculation field whenever FieldB or FieldC changes.