Extending PL/SQL language with preconditions, postconditions, and even with invariants (invariants are important for program code that uses object types, ie. classes).
The Ada programming language, which is the foundation of PL/SQL, received these new features in Ada 2012 edition:
Ada Reference Manual 2012 - Language Changes
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The following significant changes with respect to the 1995 edition as amended by Amendment 1 are incorporated:
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The concept of assertions introduced in the 2005 edition is extended with the ability to specify preconditions and postconditions for subprograms, and invariants for private types.
The concept of constraints in defining subtypes is supplemented with subtype predicates that enable subsets to be specified other than as simple ranges.
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