Language and system design

Over time we publish a number of PDF documents detailing the thinking behind the design of the Perspectives Language and the Perspectives Distributed Runtime. This collection is of interest to developers and architects. Documents new to the current release are in bold typeface.

• Assignment
• Rules
• State and dependency tracking
• State change - cache, save and sync
• Perspectives across context boundaries
• Perspectives across context boundaries
• Query Inversion
• External Function Interface
• Abstract Data Type
• The case for an object variable in rules
• Implementing the Functional Reactive Pattern
• Overview of state change mechanisms
• Revision Handling
• Locating peers
• Serialising data structures
• Synchronisation
• Compose Instance and Type Level Functions
• Indexed Names
• Expanding prefixed names
• Parsing and Compiling Models
• User and System Identifier
• The practical guide to writing a module with core external functions
• Query Inversion.
• Perspectives on Bindings
• Contextualizing
• Sync subnetworks as a consequence of a new binding
• Booting a Domain
• Who Authors
• currentcontext and currentrole
• The Case for Database Query Roles
• Keyboard alternative to drag and drop
• Become
• Creating and deleting contexts
• The Operational Meaning of a Perspective.
• Unlinked roles.
• Model versions and compatibility.
• Error handling in the PDR.
• Configuring Couchdb for Inplace 8.
• State and notification
• Understanding a Perspective model text
• Aspect States. This text describes a future extension. It is about that a modeller might want to extend the state definition of an Aspect of one of her types.
• Adding Aspect Perspectives. User roles have Perspectives. However, they can also be composed of Aspect (User) roles. What if the latter have Perspectives, too? This text explores the space of meanings we can give to such compositions and it describes the (partial) support we envision for the Perspectives Distributed Runtime.
• Binder vs Filler terminology. Unfortunately, in the implementation of the PDR we use a different set of terms for connecting roles than in the language definition.
• Aspects and role fillingIn this text we explore the consequences of the introduction of Aspect Roles for the role filling relation.
• Unlinked Roles. The modeller has the opportunity to declare a role unlinked, causing the containing context not to have direct pointers to its instances.
• Synchronisation edge cases. An exploration of difficult cases of synchronisation.
• Execution model. Exposition about the way state changing statements are executed during state transitions.
• Optimizing inverted query application In this text we describe an optimization of the functionality that applies inverted queries.
• Aspects require refinement of inverted queries. The use of Aspects requires us to rething the notion of the web of context and role types.
• Technical design standard variables. The modeller can use a number of standard variables in his expressions. The semantics of these variables is given in the text Understanding a Perspective Model Text. In this text I explain how these variables are implemented.
• Synchronization and state. The conditionality of perspectives on state affects synchronisation.

Texts that came with the latest release:

• The context with a presence pattern
• The case for an integrated editor

We also publish some more prosaic texts on project dynamics etc.

• Building a release