Collection Type in BML

Summary:

What is collection type in BML? I tried print method, get method, but nothing works. I was really surprised with print not working.

See Below:

Content (please ensure you mask any confidential information):

We have two commerce processes. We want to enable process invocation for both on favorites list. So, we will have to add condition in at least one. While adding condition, we want to use _model_product_line_var_name and _model_variable_name. But we are getting a collection in condition. We are not able to parse this.

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