A computer which executes rules which are defined according to a language having a valid grammar. The computer comprises input means for receiving and temporarily storing a first source code representation of a rule; object code translation means for translating the first source code representation into a first object code representation executable by the computer; storage means for storing the object code representations of rules; discard means for automatically discarding from the input means the first source code representation upon the storing of the first object code representation in the storage means; source code translation means for translating the first object code representation into a second source code representation where the second source code representation has lines of text; edit means for editing the second source code representation by deleting, adding, or changing one or more of the lines of text of the second source code representation; second object code translation means for translating the second source code representation, as edited, into a new object code representation of the edited rule for storage in the storage means; and the discard means discarding the first object code and second source code representations automatically upon the storing of the new object code representation of the edited rule in the storage means. The computer thereby minimizes the storage required in the storage means for storing rules and maintains version control over the object code representations of rules stored in the storage means. A method for manipulating a database of data and rules stored in a computer system where the computer operates in accordance with object-coded rules defined by a specified object code grammar. The computer including storage means for storing data and object-coded rules in tables in conformance with a storage architecture, control means for storing, retrieving and deleting data and object- coded rules from the tables, translator means for translating source-coded rules into object-coded rules, detranslator means for translating object-coded rules into source-coded rules and scanner means for determining lexical validity of an object-coded rule according to the grammar. The method first comprising the ordered steps of entering into the computer a first source-coded rule; storing the first source-coded rule into tables in the storage means; translating the first source-coded rule into a first object-coded rule; storing the first object-coded rule into the tables in the storage means; and discarding the first source-coded rule from the tables in the storage means. Secondly, the method comprises the steps of retrieving an object-coded rule from the tables in the storage means; translating the object-coded rule into a second source-coded rule; editing the second source- coded rule; storing the second source-coded rule, as edited, into the tables in the storage means; translating the second source-coded rule into a second object-coded rule; storing the second object-coded rule into the tables in the storage means and discarding the original object-coded rule and the second source-coded rule from the tables in the storage means. The method further requires that each translating step determines lexical validity or invalidity of the object-coded rule translated from the source-coded rule; that each storing step conditions the storage of an object-coded rule in the tables in the storage means upon the determination of validity of the object-coded rule to be stored and each discarding step conditions the discarding of the first source-coded rule upon the storing of said first object-coded rule into the tables in the storage means and of the original object-coded rule and the second source-coded rule upon the storing of the second object-coded rule in the tables in the storage means.