- swipl
- library
- error.pl
- debug.pl -- Print debug messages and test assertions
- apply.pl
- lists.pl -- List Manipulation
- broadcast.pl
- predicate_options.pl -- Access and analyse predicate options
- shlib.pl
- option.pl -- Option list processing
- thread_pool.pl
- gensym.pl
- settings.pl
- arithmetic.pl
- main.pl
- readutil.pl
- 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
- backcomp.pl -- Backward compatibility
- date.pl -- Process dates and times
- listing.pl -- List programs and pretty print clauses
- prolog_profile.pl -- Execution profiler
- quintus.pl -- Quintus compatibility
- shell.pl -- Elementary shell commands
- intercept.pl -- Intercept and signal interface
- wfs.pl -- Well Founded Semantics interface
- tables.pl -- XSB interface to tables
- system.pl -- System utilities
- threadutil.pl -- Interactive thread utilities
- optparse.pl -- command line parsing
- make.pl -- Reload modified source files
- writef.pl -- Old-style formatted write
- prolog_stack.pl -- Examine the Prolog stack
- prolog_versions.pl -- Demand specific (Prolog) versions
- terms.pl -- Term manipulation
- prolog_jiti.pl -- Just In Time Indexing (JITI) utilities
- files.pl
- prolog_trace.pl -- Print access to predicates
- tty.pl -- Terminal operations
- varnumbers.pl -- Utilities for numbered terms
- prolog_debug.pl -- User level debugging tools
- check.pl -- Consistency checking
- portray_text.pl -- Portray text
- ansi_term.pl -- Print decorated text to ANSI consoles
- heaps.pl -- heaps/priority queues
- strings.pl -- String utilities
- charsio.pl -- I/O on Lists of Character Codes
- edit.pl -- Editor interface
- zip.pl -- Access resource ZIP archives
- prolog_history.pl -- Per-directory persistent commandline history
- prolog_config.pl -- Provide configuration information
- streams.pl -- Manage Prolog streams
- statistics.pl -- Get information about resource usage
- codesio.pl -- I/O on Lists of Character Codes
- prolog_metainference.pl -- Infer meta-predicate properties
- prolog_coverage.pl -- Coverage analysis tool
- fastrw.pl -- Fast reading and writing of terms
- sort.pl
- qsave.pl -- Save current program as a state or executable
- prolog_autoload.pl -- Autoload all dependencies
- macros.pl -- Macro expansion
- help.pl -- Text based manual
- prolog_codewalk.pl -- Prolog code walker
- win_menu.pl -- Console window menu
- base32.pl -- Base32 encoding and decoding
- when.pl -- Conditional coroutining
- increval.pl -- Incremental dynamic predicate modification
- explain.pl -- Describe Prolog Terms
- coinduction.pl -- Co-Logic Programming
- prolog_wrap.pl -- Wrapping predicates
- hashtable.pl -- Hash tables
- 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.