pPL/pgSQL restriction on characters for copying types?

Hi

My names can contain a special character (⠒), e.g. to separate the
donator object from the name or the name from the type. Typically, I use
this with foreign keys, e.g. table PARENT has the surrogate key ID, the
table CHILD would then have the column PARENT⠒ID. That way, I can use
the underscore to segment column names like yet_another_column_name. I
do not like camel-case in that case because names do not have to be case
sensitive.

However, I want to create a (trigger) function to impose data
consistency. For that purpose, I try to copy the data type of a PL/pgSQL
variable from the base object, a view in that case. Trying so, I get the
following error on installation of the function.

V⠒NODE_TYPE⠒NAME NODE⠒V.NODE_TYPE⠒NAME%type := null;

Syntax error at "%" … invalid type name. If I use the actual type of the
column, all is fine.

V⠒NODE_TYPE⠒NAME text;

Please find attached script files of objects directly involved in the
trigger function.

Is there something, I am doing wrongly?

Kind Regards

Thiemo