Unfortunately, there's no support inside of expressions in Blue Prism for if/then/else logic at all. Also, all expression patterns and functions that are supported in Calculation/Multi-calc/Decision stages are listed in the bottom left in the Functions pane. There's more info in F1 Help inside Blue Prism under 'Calculations and Decisions'.
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Dave Morris
3Ci @ Southern Company
Atlanta, GA
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Dave Morris, 3Ci at Southern Company