| ►Implementation Considerations | This section is about the YAP implementation, and is mostly of interest to hackers |
| The Abstract Machine Emulator | |
| Short-lived memory allocation | Support for short-lived memory allocation |
| ►Memory Allocation in YAP | Memory organization and Auxiliary Memory Access Data-structures and routines |
| Using a scratch buffer | Use a scratch buffer (maybe even many), |
| Stack Discipline Memory Allocation | Memory who lives during a stack activation |
| Implementation of Blobs | |
| ►Error Handling | |
| Error Handling | The error handler is called when there is an execution error or a warning needs to be displayed |
| Exception Descriptor Manipulation | Manipulate error/throw descriptors |
| Indexing | The indexation mechanism restricts the set of clauses to be tried in a procedure by using information about the status of the instantiated arguments of the goal |
| Summary of YAP Predefined Operators | The Prolog syntax caters for operators of three main kinds: |
| Scanner Implementation. | Convert Prolog text into tokens |
| Text Processing Support Routines | Support for text processing: |
| ►An object oriented interface for YAP. | C++ wrapper to terms, predicates and queries |
| Prolog Atoms | Symbols and associated propeeties |
| Data-Base Component of YAP interface. | These classes define the main data-structures stored to represent compiled programs: |
| Error Handling in the YAP interface. | Error handling in C++ and OO languages |
| Query Handling in the YAP interface. | Engine and Query Management |
| Term Handling in the YAP interface. | These classes offer term construction and access |
| Installing YAP | |
| ►YAP Core Built-ins | |
| Predicates on Atoms and Strings | The following predicates are used to manipulate atoms, strings, lists of codes and lists of chars |
| The Blackboard | YAP implements a blackboard in the style of the SICStus Prolog blackboard |
| Copying Terms | |
| ►Internal Data Base | Some programs need global information for, e.g |
| Atom to Atomic Family of Built-ins. | Maintain a light-weight map where the key is an atom, and the value can be any constant |
| Supporting features of the Prolog language. | Prolog includes a number of features that allow program and predicate manipulation |
| ►Arithmetic in YAP | |
| Arithmetic Functions | YAP implements several arithmetic functions, they are defined as fields in three enumerations, such that there is one enumeration per each different arity:
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| Arithmetic Comparison Predicates | |
| Predicates that perform arithmetic | |
| ►Prolog Flags | |
| C-code to handle Prolog flags. | Low-level code to support flags |
| Predicates to access Prolog flags. | Following builins provide read-write access the Prolog flags |
| Prolog Support | |
| YAP Global Flags | |
| YAP Thread-local flags | Prolog flags that can take different values in different threads and/or modules |
| ►Input/Output Predicates | ⁸
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| Aliases to Stream Names | Aliases: This file defines the main operations on aliases, a second name for a file |
| Character-Based Input/Output | YAP implements most of the ISO-Prolog built-ins |
| Character Encoding and Manipulation. | The Prolog library includes a set of built-in predicates designed to support manipulation of sequences of text, represented either as lists, atoms or strings |
| Memory Streams | |
| Formatted Output | This file includes the definition of the formatted output predicates |
| Term Writing in Prolog. | %! |
| YAP Old Style Socket and Pipe Interface | Autoload the socket/pipe library |
| File and Directory Operations |
|
| File Name Resolution | Support for file name resolution through absolute_file_name/3 and friends |
| Access to Operating System Functionality | The following built-in predicates allow access to underlying Operating System functionality |
| Format | %! |
| StreamM | %! %! |
| ►Control Predicates | |
| Message Handling | The interaction between YAP and the user relies on YAP's ability to portray messages |
| Handling Undefined Procedures | A predicate in a module is said to be undefined if there are no clauses defining the predicate, and if the predicate has not been declared to be dynamic |
| Global Variables | Global variables are associations between names (atoms) and terms |
| Freeze System Configuration |
- This protects current code from further changes and also makes it impossible for some predicates to be seen in user-space
|
| Dialects | |
| Error generating type-checking | This code is based oon the SWI predicates to simplify error generation and checking |
| Grammar Rules | Grammar rules in Prolog are both a convenient way to express definite clause grammars and an extension of the well known context-free grammars |
| list predicates in a module | |
| Operators | |
| Collecting Solutions to a Goal | When there are several solutions to a goal, if the user wants to collect all the solutions he may be led to use the data base, because backtracking will forget previous solutions |
| System Status | |
| ►Term Manipulation | |
| Inlined Tests and Term Manipulation | |
| Term Visit and Manipulation | |
| Top-Level and Boot Predicates | |
| ►YAP Library | |
| Extension of arg/3 |
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| Association Maps | The following association list manipulation predicates are available once included with the use_module(library(assoc)) command |
| SWI-Like autoloader | |
| AVL Trees | Supports constructing AVL trees |
| Backtrackable Hash Tables |
|
| Block Diagram | This library provides a way of visualizing a prolog program using modules with blocks |
| Concurrent Alarms | This library provides a concurrent signals |
| Operations on Sequences of Codes. | Term to sequence of codes conversion, mostly replaced by engine code |
| Clause Manipulation | This library supports a number of useful utilities that come up over and over again when manipulating Prolog programs |
| Old Call Cleanup | % call_cleanup/1 and call_cleanup/2 allow predicates to register code for execution after the call is finished |
| Co-Logic Programming |
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| Non-backtrackable queues in YAP. | A library to implement queues of NB Terms |
| Memory Usage in Prolog Data-Base | This library provides a set of utilities for studying memory usage in YAP |
| Directed Graphs | The following graph manipulation routines use the red-black tree library to try to avoid linear-time scans of the graph for all graph operations |
| Exo Intervals | This package assumes you use exo-compilation, that is, that you loaded the pedicate using the exo option to load_files/2 , In this case, YAP includes a package for improved search on intervals of integers |
| Flag Manipulation in Prolog |
- Routines to manipulate flags: they allow defining, set, resetting
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| Generate a new symbol. |
- Predicates to create new atoms based on the prefix Atom
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| Heaps | A heap is a labelled binary tree where the key of each node is less than or equal to the keys of its sons |
| Tries for ILP | |
| MPI Interface | This library provides a set of utilities for interfacing with LAM MPI |
| Line Manipulation Utilities | This package provides a set of useful predicates to manipulate sequences of characters codes, usually first read in as a line |
| Apply a predicate to all arguments of a term | |
| ►Map List and Term Operations |
- This library provides a set of utilities for applying a predicate to all elements of a list
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| Apply Interface to maplist | This library provides a SWI-compatible set of utilities for applying a predicate to all elements of a list |
| MATLAB Package Interface | The MathWorks MATLAB is a widely used package for array processing |
| Matrix Library | This package provides a fast implementation of multi-dimensional matrices of integers and floats |
| Non-Backtrackable Data Structures | The following routines implement well-known data-structures using global non-backtrackable variables (implemented on the Prolog stack) |
| Ordered Sets | The following ordered set manipulation routines are available once included with the use_module(library(ordsets)) command |
| Automating test generation | This library aims at facilitating test generation in a logic program, namely when interfacing to foreign code |
| Queues | The following queue manipulation routines are available once included with the use_module(library(queues)) command |
| ►Random Number Generator | Since YAP-4.3.19 YAP uses the O'Keefe public-domain algorithm, based on the "Applied Statistics" algorithm AS183 |
| Pseudo Random Number Integer Generator | The following routines produce random non-negative integers in the range 0 |
| Red-Black Trees |
|
| Reading Lines and Files | Read full lines and a full file in a single call |
| Regular Expressions | This library includes routines to determine whether a regular expression matches part or all of a string |
| Range-List (RL) trees |
|
| Splay Trees | Splay trees are explained in the paper "Self-adjusting Binary Search
Trees", by D.D |
| Operating System Functionality | Portable Interaction with the OS, be it Unix, Linux, OSX, or Windows |
| Utilities On Terms | The next routines provide a set of commonly used utilities to manipulate terms |
| Calls With Timeout | The time_out/3 command relies on the alarm/3 built-in to implement a call with a maximum time of execution |
| Updatable Binary Trees | The following queue manipulation routines are available once included with the use_module(library(trees)) command |
| Trie DataStructure | Engine Independent trie library |
| Unweighted Graphs | The following graph manipulation routines are based in code originally written by Richard O'Keefe |
| Undirected Graphs | The following graph manipulation routines use the red-black tree graph library to implement undirected graphs |
| Variabilize term. | |
| Weighted Directed Graphs |
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| Weighted Graphs | Weighted Graph Processing Utilities |
| Weighted Undirected Graphs |
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| Yap PreProcessing | |
| Low-level access |
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| List Predicates in the Prolog Library |
|
| SICStus compatible socket library | Uses SWI code |
| ►YAP Extensions | |
| Named Arrays | The YAP system includes experimental support for arrays |
| Global Variables | Global variables are associations between names (atoms) and terms |
| Rational Trees | Prolog unification is not a complete implementation |
| ►Attributed Variables | |
| ►Low-level support for Attributed | Variables |
| SICStus-style Constraints in C | |
| SWI-style Constraints in C | |
| ►SICStus Style attribute declarations | |
| SICStus style attribute declarations |
|
| predicate | |
| Android Support | |
| Log Output of Tests in Markdown format. |
- These primitives support writing a user-specified log of execution to an output file
|
| Parallelism in YAP | There has been a sizeable amount of work on an or-parallel implementation for YAP, called YAPOr |
| ►Profiling Prolog Programs | YAP includes two profilers |
| Tick Profiler | The tick profiler works by interrupting the Prolog code every so often and checking at each point the code was |
| Counting Calls |
|
| The Count Profiler | The count profiler works by incrementing counters at procedure entry or backtracking |
| ►Loading files into YAP | We present the main predicates and directives available to load files and to set-up the Prolog environment |
| ►The Predicates that Read Source Files | |
| ►Directing and Configuring the Compiler | The YAP system also includes a number of primitives designed to set compiler parameters and to track the state of the compiler |
| Internal Clause Rewriting | YAP supports several clause optimisation mechanisms, that are designed to improve execution of arithmetic and term construction built-ins |
| YAP Style Checker | YAP implements a style-checker thay currently verifies whether: |
| Conditional Compilation | Conditional compilation builds on the same principle as term_expansion/2 , goal_expansion/2 and the expansion of grammar rules to compile sections of the source-code conditionally |
| Declaring Properties of Predicates | The YAP Compiler allows the programmer to include declarations with important pproprties of predicates, such as where they can be modified during execution time, whether they are meta-predicates, or whether they can be defined across multiple files |
| Conditional Compilation | Conditional compilation builds on the same principle as term_expansion/2 , goal_expansion/2 and the expansion of grammar rules to compile sections of the source-code conditionally |
| Loading Large Tables | Fast and Exo Loading % |
| ►Creating and Using a saved state | |
| C-support for saved states. | |
| ►Interacting with the debugger | Debugging with YAP is similar to debugging with C-Prolog |
| Implementation of the Debugger | Prolog code to do debugging |
| Debugger Control | The following predicates are available to control the debugging of programs: |
| Depth Limited Search | YAP implements various extensions to the default Prolog search |
| Prolog Directives | @
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| Extended Abstract Machine | |
| Compiled Form of Arithmetic Expressions in Prolog |
|
| Predicate Import Mechanism |
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| Access to Foreign Language Programs | |
| ►predicate | |
| The Module System versus the meta-call. |
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| Module Support |
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| Module Interface Predicates |
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| Configuration of the Prolog file search path | Prolog systems search follow a complex search on order to track down files |
| The Clausal Data Base | Predicates in YAP may be dynamic or static |
| Declaring a type of predicate: | |
| Tabling | YAPTab is the tabling engine that extends YAP's execution model to support tabled evaluation for definite programs |
| ►Threads | YAP implements a SWI-Prolog compatible multithreading library |
| Creating and Destroying Prolog Threads | |
| Monitoring Threads | Normal multi-threaded applications should not need these the predicates from this section because almost any usage of these predicates is unsafe |
| Signalling Threads | These predicates provide a mechanism to make another thread execute some goal as an interrupt |
| Thread Synchronisation | All internal Prolog operations are thread-safe |
| Thread communication | Prolog threads can exchange data using dynamic predicates, database records, and other globally shared data |
| Threads and Dynamic Predicates | Besides queues threads can share and exchange data using dynamic predicates |
| Or-Parallelism | @ |
| ►Arrays | |
| Implementation Notes | This file works together with pl/arrays.yap and arrays.h |
| ►ChYInterface | C-Interface to YAP |
| Term Handles or Slots | Term handles correspond to SWI-Prolog's term_t datatype: they are a safe representation of terms |
| Term Handles | Also known as term handles, slots are offsets to entries in the local stack |
| Parser Implementation | As expected for Prolog, this is a recursive top-down parser |
| YapError | The file YapErrors.h contains a list with all the error classes known internally to the YAP system |
| Rl | |
| ►Library | Read full lines and a full file in a single call |
| expressions | This library provides lambda expressions to simplify higher order programming based on call/N |
| ►SWI Compatible attributes | |
| Implementing Attributed Variables and Co-Routining |
|
| YAPTypes | |
| Comparing_Terms | |
| User Defined Extensions | User Defined Extensions |
1.9.3