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Lua as a "domain specific language"?

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Hello,
The preface to "Programming in Lua" states that "many people regard Lua not as a language, but as a kit for building domain-specific languages". Fair enough, but what does that mean in practice? What usage of Lua qualifies as "domain specific language"? Does anyone have a concrete example of using Lua for such purpose? Suspending disbelieve for an instant, one could imagine the DSL realm as something like "data definition language" or perhaps its hillbilly cousin: object-relational mapping. Bellow are a couple of syntactical example broadly dealing with the same issue of "data definition" and/or "mapping":
Oracle's SQL:
create table orders (
 order_id number,
 order_dt date,
 cust_id references customer
 constraint pk_orders (order_id)
)
Smalltalk's GLORP:
Joinfrom: (myTable fieldNamed: 'ADMIN_ID') to: (userTable fieldNamed: 'ID'))
Lisp's CLSQL:
(manager :accessor employee-manager :db-kind :join :db-info (:join-class employee :home-key managerid :foreign-key emplid :set nil))
Perl's Class::DBI:
Music::CD->has_a(artist => 'Music::Artist');
Python's SQLObject 2:
class Foo(SQLObject):
 other = Reference('Other', 'other_id')
Ruby's RoR:
class Project < ActiveRecord::Base
 belongs_to :portfolio
 has_one :project_manager
 has_many :milestones
 has_and_belongs_to_many :categories
end
Is any of the above an illustration of "domain specific language"?
What would be a "domain specific language" way to convey such information in Lua?
Does this qualify as "data manipulation language"?
local aStatement = function()
 Select()
 From( Employee )
 Where( Eq( name, "Vladimir" ), Eq( city, "Moskva" ) )
 Order( By( name ) )
end
Could this be a "data definition language"?
local aModel = function()
 Is( Employee, hr.v_employee )
 Has( name, string )
 HasOne( manager, Manager )
 HasMany( colleagues, Employee )
end
Confused :/
Cheers
--
PA, Onnay Equitursay
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