Constant declaration

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constant_decl = CONSTANT constant_body { constant_body } END_CONSTANT ';' .
constant_body = constant_id ':' base_type ':=' expression ';' .
Unlike in the EXPRESS language, the constant declaration must not be the very first declaration. There can be any number of constant declarations in an EDMexpressX^ mapping schema, and they can be placed anywhere after the global declaration.
In the same way there are no restrictions on the number of constant declarations, or the order of the constant declarations, within an algorithm head declaration.
The scope of a constant identifier is the schema, function, procedure, map, statements or compose declaration in which the constant declaration occurs.