Online "Book Flights" facility for an airline

Metarules

Rule type Template Metarules
Mandatory data item rule   <cardinality> ::=
    {exactly <positive integer>|
    at least <positive integer>
    {and at most <positive integer>|}}
RT39 for data items that are part of complex data items
RT38 for other data items
Mandatory option selection rule RT16  
Mandatory group rule RT17 if either or both of 2 items in the group
RT18 if only 1 of 2 items in the group
RT19 if more than 2 items in the group
Prohibited data rule RT20  
Singular data rule   <cardinality> ::= {exactly|at most} one
RT39 for data items that are part of complex data items
RT38 for other data items
Dependent cardinality rule RT27 <set function> ::= number
Structural cardinality rule RT36  
Value set rule RT21 <predicate> ::= <value predicate>
if only 1 data item
RT22 <combination predicate> ::= <combination value set predicate>
if combination of data items
Match rule (operative) RT21 <predicate> ::= <match predicate>
Match rule (structural) RT26 <predicate> ::= <match predicate>
Range rule RT21 <predicate> ::= <range predicate>
Uniqueness constraint RT21 <predicate> ::= <uniqueness predicate>
if only 1 data item
RT22

<combination predicate> ::= <combination uniqueness predicate>
if combination of data items

Set constraint (operative) RT28  
Set constraint (structural) RT29  
Definitional rule RT25  
Inter-process interval rule RT34 if rule statement expresses obligation (must)
RT35

if rule statement expresses restricted permission (may only)

Prerequisite process rule RT32  
Other process pre-condition RT33  
Data type definition rule RT37  
Data item format rule RT21 <predicate> ::= <format predicate>
Party restriction rule RT40  
Role separation rule RT41 with must not
Role binding rule RT41 with must