Creating relation between fields

Since r1635+

you can use other fields values inside
1. open/close field text parameters and
2. prefix / suffix value parameters

by entering replacements like:
{{fieldvalue##nn}} ,
{{fieldvalue##nn##propertyname}}

-- e.g for single property fields (text,date, etc) :
{{field19##0}}

-- e.g. for multi-property fields (weblink,email, etc) :
{{field19##0##link}} and {{field19##0##addr}}

-- e.g. for indexable field that have value (=index) and label (select, selectmultiple, radio, checkbox, radioimage, checkboximage, etc) :
{{field21##0##_value_}} or {{field21##0##_text_}} or {{field21##0##_image_}}