User Tools

Site Tools


at:tutorial:appendix

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
Next revision
Previous revision
at:tutorial:appendix [2020/04/28 19:44]
elisag adding
at:tutorial:appendix [2021/09/24 10:28] (current)
elisag [Dynamic Variables]
Line 392: Line 392:
 ===== Language Extensions ===== ===== Language Extensions =====
  
-The files in the ''at/lang'' directory define custom language features which mostly use AmbientTalk/2's reflective facilities to extend the language.+The files in the ''at/lang'' directory define custom language features which mostly use AmbientTalk/2's reflective facilities to extend the language. In what follows, we describe the most relevant ones
  
  
  
 +
 +=====Futures and Multifutures =====
  
 ==== Futures ==== ==== Futures ====
Line 494: Line 496:
  
  
-==== Leased Object References ====+===== Leased Object References =====
  
 The module ''/.at.lang.leasedrefs'' provides support for leased object references. Leased object references have already been described as part of the [[:at:tutorial:distribution#dealing_with_permanent_failures|distributed programing]] section in the tutorial. The module ''/.at.lang.leasedrefs'' provides support for leased object references. Leased object references have already been described as part of the [[:at:tutorial:distribution#dealing_with_permanent_failures|distributed programing]] section in the tutorial.
Line 523: Line 525:
  
  
-==== TOTAM ==== 
- 
-The module ''/.at.lang.totam'' provides support for communication using. 
  
-Please have a look to [[:uf:totam]] for further details.+===== TOTAM =====
  
 +The module ''/.at.lang.totam'' provides an implementation for TOTAM, a tuple space model geared towards mobile ad hoc networks which combines a replication-based tuple space model with a dynamic scoping mechanism that limits the transportation of tuples. 
  
 +Please have a look to [[:uf:totam]] for further details on the model and its API.
  
-==== Dynamic Variables ====+===== Dynamic Variables =====
  
 The module ''/.at.lang.dynvars'' provides support for defining and using 'Dynamic Variables'. Dynamic variables 'simulate' dynamically scoped variables and are often used to parameterize large parts of code. For example, the 'current output stream'. A dynamic variable has the advantage over a simple global variable that it can only be assigned a value for the extent of a block of code. The module ''/.at.lang.dynvars'' provides support for defining and using 'Dynamic Variables'. Dynamic variables 'simulate' dynamically scoped variables and are often used to parameterize large parts of code. For example, the 'current output stream'. A dynamic variable has the advantage over a simple global variable that it can only be assigned a value for the extent of a block of code.
Line 558: Line 559:
 You can find more usage examples of dynamic variables in the unit test included in the file ''at/lang/dynvars.at''. You can find more usage examples of dynamic variables in the unit test included in the file ''at/lang/dynvars.at''.
  
-==== Ambient References ====+===== Ambient References =====
  
 Ambient references are defined in the module ''/.at.lang.ambientrefs'' . An ambient reference is a special kind of far reference which refers to an ever-changing collection of objects of a certain type. For example: Ambient references are defined in the module ''/.at.lang.ambientrefs'' . An ambient reference is a special kind of far reference which refers to an ever-changing collection of objects of a certain type. For example:
Line 572: Line 573:
 Ambient references ship with two so-called "implementation modules": the module ''/.at.ambient.ar_extensional_impl'' and the module ''/.at.m2mi.ar_intensional_impl''. By default, the extensional implementation is used, but this can be changed by passing the desired implementation module as a parameter to the ''/.at.lang.ambientrefs'' module. Ambient references ship with two so-called "implementation modules": the module ''/.at.ambient.ar_extensional_impl'' and the module ''/.at.m2mi.ar_intensional_impl''. By default, the extensional implementation is used, but this can be changed by passing the desired implementation module as a parameter to the ''/.at.lang.ambientrefs'' module.
  
-==== Structural Types ====+===== Structural Types =====
  
 The module ''/.at.lang.structuraltypes'' implements a small library to use structural typing. The library allows for the creation of 'protocols', which are first-class structural types. A structural type is simply a set of selectors. An object o conforms to a protocol P <=> for all selectors s of P, o respondsTo s where respondsTo is determined by o's mirror. The module ''/.at.lang.structuraltypes'' implements a small library to use structural typing. The library allows for the creation of 'protocols', which are first-class structural types. A structural type is simply a set of selectors. An object o conforms to a protocol P <=> for all selectors s of P, o respondsTo s where respondsTo is determined by o's mirror.
Line 609: Line 610:
 More usage examples of structural types can be found in the unit test defined in the file ''at/lang/structuraltypes.at''. More usage examples of structural types can be found in the unit test defined in the file ''at/lang/structuraltypes.at''.
  
-==== Traits ====+===== Traits =====
  
 The module ''/.at.lang.traits'' exports a small library to use AmbientTalk's traits in a more structured manner. In the literature, traits are described as reusable components with two interfaces: an interface of methods that are //provided// by the trait //to// the composite and an interface of methods that are //required// by the trait //from// the composite. AmbientTalk's traits only make the provided interface explicit. The required interface remains implicit and unchecked at composition time. The module ''/.at.lang.traits'' exports a small library to use AmbientTalk's traits in a more structured manner. In the literature, traits are described as reusable components with two interfaces: an interface of methods that are //provided// by the trait //to// the composite and an interface of methods that are //required// by the trait //from// the composite. AmbientTalk's traits only make the provided interface explicit. The required interface remains implicit and unchecked at composition time.
at/tutorial/appendix.1588095873.txt.gz ยท Last modified: 2020/04/28 19:47 (external edit)