- swipl
- library
- error.pl
- debug.pl -- Print debug messages and test assertions
- apply.pl -- Apply predicates on a list
- lists.pl -- List Manipulation
- broadcast.pl -- Event service
- predicate_options.pl -- Access and analyse predicate options
- shlib.pl -- Utility library for loading foreign objects (DLLs, shared objects)
- option.pl
- thread_pool.pl
- gensym.pl
- settings.pl
- arithmetic.pl
- main.pl -- Provide entry point for scripts
- readutil.pl -- Read utilities
- operators.pl -- Manage operators
- pairs.pl -- Operations on key-value lists
- prolog_source.pl -- Examine Prolog source-files
- quasi_quotations.pl -- Define Quasi Quotation syntax
- url.pl -- Analysing and constructing URL
- www_browser.pl -- Open a URL in the users browser
- prolog_colour.pl
- record.pl -- Access compound arguments by name
- prolog_xref.pl -- Prolog cross-referencer data collection
- occurs.pl -- Finding and counting sub-terms
- ordsets.pl -- Ordered set manipulation
- assoc.pl -- Binary associations
- ugraphs.pl -- Graph manipulation library
- iostream.pl -- Utilities to deal with streams
- atom.pl -- Operations on atoms
- prolog_pack.pl -- A package manager for Prolog
- solution_sequences.pl -- Modify solution sequences
- git.pl -- Run GIT commands
- ctypes.pl -- Character code classification
- utf8.pl -- UTF-8 encoding/decoding on lists of character codes.
- base64.pl -- Base64 encoding and decoding
- persistency.pl -- Provide persistent dynamic predicates
- pure_input.pl -- Pure Input from files and streams
- nb_set.pl -- Non-backtrackable sets
- aggregate.pl -- Aggregation operators on backtrackable predicates
- csv.pl -- Process CSV (Comma-Separated Values) data
- dialect.pl -- Support multiple Prolog dialects
- apply_macros.pl -- Goal expansion rules to avoid meta-calling
- yall.pl -- Lambda expressions
- prolog_code.pl -- Utilities for reasoning about code
- dif.pl -- The dif/2 constraint
- thread.pl -- High level thread primitives
- rbtrees.pl -- Red black trees
- nb_rbtrees.pl -- Non-backtrackable operations on red black trees
- random.pl -- Random numbers
- sandbox.pl -- Sandboxed Prolog code
- prolog_format.pl -- Analyse format specifications
- pprint.pl -- Pretty Print Prolog terms
- modules.pl -- Module utility predicates
- lazy_lists.pl -- Lazy list handling
- edinburgh.pl -- Some traditional Edinburgh predicates
- prolog_clause.pl -- Get detailed source-information about a clause
- prolog_breakpoints.pl -- Manage Prolog break-points
- dicts.pl -- Dict utilities
- check.pl -- Consistency checking
- ansi_term.pl -- Print decorated text to ANSI consoles
- backcomp.pl -- Backward compatibility
- writef.pl -- Old-style formatted write
- charsio.pl -- I/O on Lists of Character Codes
- sort.pl
- base32.pl -- Base32 encoding and decoding
- tables.pl -- XSB interface to tables
- statistics.pl -- Get information about resource usage
- varnumbers.pl -- Utilities for numbered terms
- prolog_jiti.pl -- Just In Time Indexing (JITI) utilities
- intercept.pl -- Intercept and signal interface
- terms.pl -- Term manipulation
- quintus.pl -- Quintus compatibility
- codesio.pl -- I/O on Lists of Character Codes
- prolog_debug.pl -- User level debugging tools
- listing.pl -- List programs and pretty print clauses
- make.pl -- Reload modified source files
- increval.pl -- Incremental dynamic predicate modification
- strings.pl -- String utilities
- date.pl -- Process dates and times
- help.pl -- Text based manual
- prolog_wrap.pl -- Wrapping predicates
- rwlocks.pl -- Read/write locks
- shell.pl -- Elementary shell commands
- explain.pl -- Describe Prolog Terms
- threadutil.pl -- Interactive thread utilities
- prolog_versions.pl -- Demand specific (Prolog) versions
- wfs.pl -- Well Founded Semantics interface
- optparse.pl -- command line parsing
- prolog_profile.pl -- Execution profiler
- qsave.pl -- Save current program as a state or executable
- zip.pl -- Access resource ZIP archives
- heaps.pl -- heaps/priority queues
- prolog_history.pl -- Per-directory persistent commandline history
- when.pl -- Conditional coroutining
- prolog_trace.pl -- Print access to predicates
- edit.pl -- Editor interface
- prolog_stack.pl -- Examine the Prolog stack
- prolog_codewalk.pl -- Prolog code walker
- prolog_metainference.pl -- Infer meta-predicate properties
- prolog_coverage.pl -- Coverage analysis tool
- macros.pl -- Macro expansion
- exceptions.pl -- Exception classification
- oset.pl -- Ordered set manipulation
- hashtable.pl -- Hash tables
- coinduction.pl -- Co-Logic Programming
- system.pl -- System utilities
- prolog_autoload.pl -- Autoload all dependencies
- prolog_config.pl -- Provide configuration information
- portray_text.pl -- Portray text
- win_menu.pl -- Console window menu
- tty.pl -- Terminal operations
- fastrw.pl -- Fast reading and writing of terms
- files.pl
- library
- concurrent(+N, :Goals, +Options) is semidet
- Run Goals in parallel using N threads. This call blocks until
all work has been done. The Goals must be independent. They
should not communicate using shared variables or any form of
global data. All Goals must be thread-safe.
Execution succeeds if all goals have succeeded. If one goal fails or throws an exception, other workers are abandoned as soon as possible and the entire computation fails or re-throws the exception. Note that if multiple goals fail or raise an error it is not defined which error or failure is reported.
On successful completion, variable bindings are returned. Note however that threads have independent stacks and therefore the goal is copied to the worker thread and the result is copied back to the caller of concurrent/3.
Choosing the right number of threads is not always obvious. Here are some scenarios:
- If the goals are CPU intensive and normally all succeeding, typically the number of CPUs is the optimal number of threads. Less does not use all CPUs, more wastes time in context switches and also uses more memory.
- If the tasks are I/O bound the number of threads is typically higher than the number of CPUs.
- If one or more of the goals may fail or produce an error, using a higher number of threads may find this earlier.
- Arguments:
-
N - Number of worker-threads to create. Using 1, no threads are created. If N is larger than the number of Goals we create exactly as many threads as there are Goals. Goals - List of callable terms. Options - Passed to thread_create/3 for creating the workers. Only options changing the stack-sizes can be used. In particular, do not pass the detached or alias options. - See also
- - In many cases, concurrent_maplist/2 and friends is easier to program and is tractable to program analysis.