What is the meaning and syntax of the 'ATTR TYPE MAP' 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 'ATTR TYPE MAP' directive in FME Plugin Reader Writer metafiles and in which cases should we use it?

A) This section tells FME all the possible attribute types this format supports. It is important that this have a full mapping for the generic FME types, as if FME cannot map a generic type (say, fme_char) bad things will happen.