An expression is a combination of field references, literal values, and operators that, when evaluated, produce a single value.

 

Pulpstream uses the MVEL language to specify expressions:

      https://en.wikisource.org/wiki/MVEL_Language_Guide

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Expression Variables 

Any field present in one of the stream's data components can be accessed using the format DataComponentName.FieldName

So an Incident_Date field defined in the Incident document can be accessed by specifying Incident.Incident_Date

 

If that field happens to reference a Smart Object record, then you add a dot and another field name to reference a field in that object. For example Incident.Client.Site. References can continue cascading in that manner so, for example, to get (or modify) a risk score for that site, you might reference Incident.Client.Site.Risk_Score.

 

Of course, in the Pulpstream interface, you never have to remember references of that kind. You just click the magnifier icon next to the expression window, and select the fields you want to reference. The reference you need is then popped into the expression for you. (But now you know what you're seeing in the expression window.)

 

To write an expression:

• Click the magnifier icon next to an expression window to choose fields and insert them into the expression.
• Add numbers and numeric operators normally. For example: 3 + 5
• Put strings in single quotes. Use the "plus" operator to concatenate strings and fields.
  For example: 'Your text'+SomeDataComponent.someField
• If you need to put a single quote in the text, use the backslash escape character.
  For example: 'This was Henry\'s idea.', which becomes: This was Henry's idea.
• Click Help with Expressions to get a list of functions you can use in the expression.

To test an expression:

1. Click the checkmark icon next to the expression field.
2. Select a record to use for testing, or specify ad hoc data (you are prompted to enter values for each incoming field).