What is the meaning and syntax of the 'CORR LINE TEMPLATE' directive in FME Plugin Reader Writer metafiles and in which cases should we use it

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Q) What is the meaning and syntax of the 'CORR LINE TEMPLATE' directive in FME Plugin Reader Writer metafiles and in which cases should we use it?

A) In general, correlation lines define how to transfer source attributes into destination attributes. The CORR_LINE_TEMPLATE defines items that must be present on each correlation line. For most formats, this line will look like

CORR_LINE_TEMPLATE {FME_GEN_GROUP_NAME} <format type> {FME_GEN_GEOMETRY}

where <format type> is the attribute for your format that distinguishes between different types of features. For example, the geodatabase reader/writer uses the attribute geodb_type to distinguish between points (geodb_type = geodb_point) from lines (geodb_type = geodb_polyline) and other geometries.

NB: This directive is only used by the FME Universal Translator, not by Workbench, and by generating mapping files.