library

Prolog files

aggregate.pl  -- Aggregation operators on backtrackable predicates
ansi_term.pl  -- Print decorated text to ANSI consoles
apply.pl
convlist/3	Similar to maplist/3, but elements for which call(Goal, ElemIn, _) fails are omitted from ListOut.
exclude/3	Filter elements for which Goal fails.
foldl/4	Fold an ensemble of m (0 <= m <= 4) lists of length n head-to-tail ("fold-left"), using columns of m list elements as arguments for Goal.
foldl/5	Fold an ensemble of m (0 <= m <= 4) lists of length n head-to-tail ("fold-left"), using columns of m list elements as arguments for Goal.
foldl/6	Fold an ensemble of m (0 <= m <= 4) lists of length n head-to-tail ("fold-left"), using columns of m list elements as arguments for Goal.
foldl/7	Fold an ensemble of m (0 <= m <= 4) lists of length n head-to-tail ("fold-left"), using columns of m list elements as arguments for Goal.
include/3	Filter elements for which Goal succeeds.
maplist/2	True if Goal is successfully applied on all matching elements of the list.
maplist/3	True if Goal is successfully applied on all matching elements of the list.
maplist/4	True if Goal is successfully applied on all matching elements of the list.
maplist/5	True if Goal is successfully applied on all matching elements of the list.
partition/4	Filter elements of List according to Pred.
partition/5	Filter List according to Pred in three sets.
scanl/4	Scan an ensemble of m (0 <= m <= 4) lists of length n head-to-tail ("scan-left"), using columns of m list elements as arguments for Goal.
scanl/5	Scan an ensemble of m (0 <= m <= 4) lists of length n head-to-tail ("scan-left"), using columns of m list elements as arguments for Goal.
scanl/6	Scan an ensemble of m (0 <= m <= 4) lists of length n head-to-tail ("scan-left"), using columns of m list elements as arguments for Goal.
scanl/7	Scan an ensemble of m (0 <= m <= 4) lists of length n head-to-tail ("scan-left"), using columns of m list elements as arguments for Goal.
apply_macros.pl  -- Goal expansion rules to avoid meta-calling
apply_macros_sentinel/0	Used to detect that library(apply_macros) is loaded into the current context explicitly.
expand_phrase/2	Provide goal-expansion for PhraseGoal.
expand_phrase/4	Provide goal-expansion for PhraseGoal.
arithmetic.pl
arithmetic_expression_value/2	True when Result unifies with the arithmetic result of evaluating Expression.
arithmetic_function/1	Declare a predicate as an arithmetic function.
assoc.pl  -- Binary associations
atom.pl  -- Operations on atoms
backcomp.pl  -- Backward compatibility
base32.pl  -- Base32 encoding and decoding
base64.pl  -- Base64 encoding and decoding
broadcast.pl  -- Event service
charsio.pl  -- I/O on Lists of Character Codes
check.pl  -- Consistency checking
codesio.pl
format_to_codes/3	Use format/2 to write to a list of character codes.
format_to_codes/4	Use format/2 to write to a difference list of character codes.
open_codes_stream/2	Open Codes as an input stream.
read_from_codes/2	Read Codes into Term.
read_term_from_codes/3	Read Codes into Term.
with_output_to_codes/2	Run Goal with as once/1.
with_output_to_codes/3	Run Goal with as once/1.
with_output_to_codes/4	As with_output_to_codes/3, but Stream is unified with the temporary stream.
write_term_to_codes/3	True when Codes is a string that matches the output of write_term/3 using Options.
write_term_to_codes/4	True when Codes\Tail is a difference list containing the character codes that matches the output of write_term/3 using Options.
write_to_codes/2	Codes is a list of character codes produced by write/1 on Term.
write_to_codes/3	Codes is a difference-list of character codes produced by write/1 on Term.
coinduction.pl  -- Co-Logic Programming
csv.pl  -- Process CSV (Comma-Separated Values) data
ctypes.pl
is_digit/3	Succeeds if `C' is a digit using `Base' as base and `Weight' represents its value.
is_paren/2	True if Open is the open-parenthesis of Close.
to_lower/2	Downcase a character code.
to_upper/2	Upcase a character code.
upper_lower/2	True when U is the character code of an uppercase character and L is the character code of the corresponding lowercase character.
date.pl  -- Process dates and times
debug.pl
assertion_failed/2	This hook is called if the Goal of assertion/1 fails.
debug_print_hook/3	Hook called by debug/3.
assertion/1	Acts similar to C assert() macro.
debug/1	Add/remove a topic from being printed.
debug/3	Format a message if debug topic is enabled.
debug_message_context/1	Specify additional context for debug messages.
debugging/1	Examine debug topics.
debugging/2	Examine debug topics.
list_debug_topics/0	List currently known topics for debug/3 and their setting.
list_debug_topics/1	List currently known topics for debug/3 and their setting.
nodebug/1	Add/remove a topic from being printed.
dialect.pl  -- Support multiple Prolog dialects
dicts.pl
dict_fill/4	Implementation for the dicts_to_same_keys/3 OnEmpty closure that fills new cells with a copy of ValueIn.
dict_keys/2	True when Keys is an ordered set of the keys appearing in Dict.
dict_size/2	True when KeyCount is the number of keys in Dict.
dicts_join/3	Join dicts in Dicts that have the same value for Key, provided they do not have conflicting values on other keys.
dicts_join/4	Join two lists of dicts (Dicts1 and Dicts2) on Key.
dicts_same_keys/2	True if List is a list of dicts that all have the same keys and Keys is an ordered set of these keys.
dicts_same_tag/2	True when List is a list of dicts that all have the tag Tag.
dicts_slice/3	DictsOut is a list of Dicts only containing values for Keys.
dicts_to_compounds/4	True when Dicts and Compounds are lists of the same length and each element of Compounds is a compound term whose arguments represent the values associated with the corresponding keys in Keys.
dicts_to_same_keys/3	DictsOut is a copy of DictsIn, where each dict contains all keys appearing in all dicts of DictsIn.
mapdict/2	True when all dicts have the same set of keys and call(Goal, Key, V1, ...) is true for all keys in the dicts.
mapdict/3	True when all dicts have the same set of keys and call(Goal, Key, V1, ...) is true for all keys in the dicts.
mapdict/4	True when all dicts have the same set of keys and call(Goal, Key, V1, ...) is true for all keys in the dicts.
dif.pl  -- The dif/2 constraint
edinburgh.pl  -- Some traditional Edinburgh predicates
edit.pl
edit/0	Edit associated or script file.
edit/1	Edit indicated object.
edit_command/2	This predicate should specify the shell-command called to invoke the user's editor.
locate/2	Locate object from the specified location.
locate/3
select_location/3
error.pl
explain.pl
explain/1	Give an explanation on Term.
explain/2	True when Explanation is an explanation of Term.
fastrw.pl  -- Fast reading and writing of terms
gensym.pl  -- Generate unique symbols
git.pl
git/2	Run a GIT command.
git_branches/2	True when Branches is the list of branches in the repository.
git_default_branch/2	True when BranchName is the current branch of a repository.
git_default_branch/2	True when BranchName is the default branch of a repository.
git_describe/2	Describe the running version based on GIT tags and hashes.
git_hash/2	Return the hash of the indicated object.
git_ls_remote/3	Execute git ls-remote against the remote repository to fetch references from the remote.
git_ls_tree/2	True when Entries is a list of entries in the the GIT repository, Each entry is a term:.
git_open_file/4	Open the file File in the given bare GIT repository on the given branch (treeisch).
git_process_output/3	Run a git-command and process the output with OnOutput, which is called as call(OnOutput, Stream).
git_remote_branches/2	Exploit git_ls_remote/3 to fetch the branches from a remote repository without downloading it.
git_remote_url/3	URL is the remote (fetch) URL for the given Remote.
git_shortlog/3	Fetch information like the GitWeb change overview.
git_show/4	Fetch info from a GIT commit.
git_tags/2	True when Tags is a list of git tags defined on the repository.
git_tags_on_branch/3	Tags is a list of tags in Branch on the GIT repository Dir, most recent tag first.
is_git_directory/1	True if Directory is a git directory (Either checked out or bare).
is_git_hash/1	True when Atom represents a GIT hash, i.e., a 40 digit hexadecimal string.
heaps.pl  -- heaps/priority queues
help.pl
apropos/1	Print objects from the manual whose name or summary match with Query.
help/0	Show help for What.
help/1	Show help for What.
help_text/2	When Predicate is a term of the form Name/Arity for which documentation exists, HelpText is the documentation in textual format (parsed from the HTML help).
show_html_hook/1	Hook called to display the extracted HTML document.
increval.pl  -- Incremental dynamic predicate modification
intercept.pl
intercept/3	Run Goal as call/1.
intercept/4	Similar to intercept/3, but the copy of Handler is called as call(Copy,Arg), which allows passing large context arguments or arguments subject to unification or destructive assignment.
intercept_all/4	True when List contains all instances of Template that have been sent using send_signal/1 where the argument unifies with Ball.
nb_intercept_all/4	As intercept_all/4, but backtracing inside Goal does not reset List.
send_signal/1	If this predicate is called from a sub-goal of intercept/3, execute the associated Handler of the intercept/3 environment.
send_silent_signal/1	As send_signal/1, but succeed silently if there is no matching intercept environment.
iostream.pl  -- Utilities to deal with streams
close_any/1	Execute the Close closure returned by open_any/5.
open_any/5	Establish a stream from Specification that should be closed using Close, which can either be called or passed to close_any/1.
lazy_lists.pl  -- Lazy list handling
listing.pl
listing/0	Lists all predicates defined in the calling module.
listing/1	List matching clauses.
listing/2	List matching clauses.
portray_clause/1	Portray `Clause' on the current output stream.
portray_clause/2	Portray `Clause' on the current output stream.
portray_clause/3	Portray `Clause' on the current output stream.
lists.pl
append/2	Concatenate a list of lists.
append/3	List1AndList2 is the concatenation of List1 and List2.
clumped/2	Pairs is a list of Item-Count pairs that represents the run length encoding of Items.
delete/3	Delete matching elements from a list.
flatten/2	Is true if FlatList is a non-nested version of NestedList.
intersection/3	True if Set3 unifies with the intersection of Set1 and Set2.
is_set/1	True if Set is a proper list without duplicates.
last/2	Succeeds when Last is the last element of List.
list_to_set/2	True when Set has the same elements as List in the same order.
max_list/2	True if Max is the largest number in List.
max_member/2	True when Max is the largest member in the standard order of terms.
max_member/3	True when Max is the largest member according to Pred, which must be a 2-argument callable that behaves like (@=<)/2.
member/2	True if Elem is a member of List.
min_list/2	True if Min is the smallest number in List.
min_member/2	True when Min is the smallest member in the standard order of terms.
min_member/3	True when Min is the smallest member according to Pred, which must be a 2-argument callable that behaves like (@=<)/2.
nextto/3	True if Y directly follows X in List.
nth0/3	True when Elem is the Index'th element of List.
nth0/4	Select/insert element at index.
nth1/3	Is true when Elem is the Index'th element of List.
nth1/4	As nth0/4, but counting starts at 1.
numlist/3	List is a list [Low, Low+1, ... High].
permutation/2	True when Xs is a permutation of Ys.
prefix/2	True iff Part is a leading substring of Whole.
proper_length/2	True when Length is the number of elements in the proper list List.
reverse/2	Is true when the elements of List2 are in reverse order compared to List1.
same_length/2	Is true when List1 and List2 are lists with the same number of elements.
select/3	Is true when List1, with Elem removed, results in List2.
select/4	Select from two lists at the same position.
selectchk/3	Semi-deterministic removal of first element in List that unifies with Elem.
selectchk/4	Semi-deterministic version of select/4.
subseq/3	Is true when SubList contains a subset of the elements of List in the same order and Complement contains all elements of List not in SubList, also in the order they appear in List.
subset/2	True if all elements of SubSet belong to Set as well.
subtract/3	Delete all elements in Delete from Set.
sum_list/2	Sum is the result of adding all numbers in List.
union/3	True if Set3 unifies with the union of the lists Set1 and Set2.
macros.pl
expand_macros/5	Perform macro expansion on TermIn with layout PosIn to produce TermOut with layout PosOut.
include_macros/3	Include macros from another module.
macro_position/1	True when Position is the position of the macro.
main.pl  -- Provide entry point for scripts
make.pl  -- Reload modified source files
modules.pl  -- Module utility predicates
nb_set.pl
add_nb_set/2	Insert Key into the set.
add_nb_set/3	Insert Key into the set.
empty_nb_set/1	Create an empty non-backtrackable set.
gen_nb_set/2	Enumerate the members of a set in the standard order of terms.
nb_set_to_list/2	Get the elements of a an nb_set.
size_nb_set/2	Unify Size with the number of elements in the set.
occurs.pl  -- Finding and counting sub-terms
operators.pl
pop_operators/0	Revert all changes to the operator table realised since the last push_operators/1.
pop_operators/1	Reset operators as pushed by push_operators/2.
push_op/3	As op/3, but this call must appear between push_operators/1 and pop_operators/0.
push_operators/1	Installs the operators from New, where New is a list of op(Prec, Type, :Name).
push_operators/2	Installs the operators from New, where New is a list of op(Prec, Type, :Name).
option.pl
dict_options/2	Convert between an option list and a dictionary.
merge_options/3	Merge two option sets.
meta_options/3	Perform meta-expansion on options that are module-sensitive.
option/2	Get an Option from Options.
option/3	Get an Option from Options.
select_option/3	Get and remove Option from Options.
select_option/4	Get and remove Option with default value.
optparse.pl  -- command line parsing
ordsets.pl
is_ordset/1	True if Term is an ordered set.
list_to_ord_set/2	Transform a list into an ordered set.
ord_add_element/3	Insert an element into the set.
ord_del_element/3	Delete an element from an ordered set.
ord_disjoint/2	True if Set1 and Set2 have no common elements.
ord_empty/1	True when List is the empty ordered set.
ord_intersect/2	True if both ordered sets have a non-empty intersection.
ord_intersect/3	Intersection holds the common elements of Set1 and Set2.
ord_intersection/2	Intersection of a powerset.
ord_intersection/3	Intersection holds the common elements of Set1 and Set2.
ord_intersection/4	Intersection and difference between two ordered sets.
ord_memberchk/2	True if Element is a member of OrdSet, compared using ==.
ord_selectchk/3	Selectchk/3, specialised for ordered sets.
ord_seteq/2	True if Set1 and Set2 have the same elements.
ord_subset/2	Is true if all elements of Sub are in Super.
ord_subtract/3	Diff is the set holding all elements of InOSet that are not in NotInOSet.
ord_symdiff/3	Is true when Difference is the symmetric difference of Set1 and Set2.
ord_union/2	True if Union is the union of all elements in the superset SetOfSets.
ord_union/3	Union is the union of Set1 and Set2.
ord_union/4	True iff ord_union(Set1, Set2, Union) and ord_subtract(Set2, Set1, New).
pairs.pl  -- Operations on key-value lists
persistency.pl  -- Provide persistent dynamic predicates
pio.pl  -- Pure I/O
portray_text.pl
portray_text/1	Switch portraying on or off.
set_portray_text/2	Set options for portraying.
set_portray_text/3	Set options for portraying.
pprint.pl  -- Pretty Print Prolog terms
predicate_options.pl  -- Access and analyse predicate options
prolog_autoload.pl
autoload_all/0	Force all necessary autoloading to be done now.
autoload_all/1	Force all necessary autoloading to be done now.
prolog_breakpoints.pl  -- Manage Prolog break-points
prolog_clause.pl
clause_info/4	Fetches source information for the given clause.
clause_info/5	Fetches source information for the given clause.
clause_name/2	Provide a suitable description of the indicated clause.
initialization_layout/4	Find term-layout of :- initialization directives.
make_varnames/5	Create a Term varnames(...) where each argument contains the name of the variable at that offset.
open_source/2	Hook into clause_info/5 that opens the stream holding the source for a specific clause.
predicate_name/2	Describe a predicate as [Module:]Name/Arity.
unify_goal/5	This hook is called to fix up source code manipulations that result from goal expansions.
unify_term/2	Unify the two terms, where T2 is created by writing the term and reading it back in, but be aware that rounding problems may cause floating point numbers not to unify.
prolog_code.pl
body_term_calls/2	True when BodyTerm calls Goal.
comma_list/2	True if CommaList is a nested term over the ','/2 (';'/2) functor and List is a list expressing the elements of the conjunction.
extend_goal/3	Extend the possibly qualified Goal0 with additional arguments from Extra.
head_name_arity/3	Similar to functor/3, but deals with SWI-Prolog's zero-argument callable terms and avoids creating a non-callable term if Name is not an atom and Arity is zero.
is_control_goal/1	True if Goal is a compiled Prolog control structure.
is_predicate_indicator/1	True when Term is a predicate indicator.
mkconj/3	Create a conjunction or disjunction from two terms.
mkdisj/3	Create a conjunction or disjunction from two terms.
most_general_goal/2	General is the most general version of Goal.
pi_head/2	Translate between a PredicateIndicator and a Goal term.
predicate_label/2	Create a human-readable label for the given predicate indicator.
predicate_sort_key/2	Key is the (module-free) name of the predicate for sorting purposes.
semicolon_list/2	True if CommaList is a nested term over the ','/2 (';'/2) functor and List is a list expressing the elements of the conjunction.
prolog_codewalk.pl  -- Prolog code walker
prolog_colour.pl
prolog_colourise_query/3	Colourise a query, to be executed in the context of SourceId.
prolog_colourise_stream/3	Determine colour fragments for the data on Stream.
prolog_colourise_stream/4	Determine colour fragments for the data on Stream.
prolog_colourise_term/4	Colourise the next term on Stream.
syntax_colour/2	True when a range classified Class must be coloured using Attributes.
vararg_goal_classification/3	Multifile hookable classification for vararg predicates.
prolog_config.pl
prolog_config/2	Get information on the configuration of the current Prolog system.
prolog_dump_runtime_variables/0	Dump the current configuration in shell format.
prolog_coverage.pl  -- Coverage analysis tool
prolog_debug.pl
debug_control_hook/1	Allow user-hooks in the Prolog debugger interaction.
debugging/0	Report current status of the debugger.
debugging_hook/1	Multifile hook that is called as forall(debugging_hook(DebugMode), true) and that may be used to extend the information printed from other debugging libraries.
exception_hook/5	Trap exceptions and consider whether or not to start the tracer.
nospy/1	Set/clear spy-points.
nospyall/0	Set/clear spy-points.
notrap/1	Install a trap on error(Formal, Context) exceptions that unify.
spy/1	Set/clear spy-points.
trap/1	Install a trap on error(Formal, Context) exceptions that unify.
trap_alias/2	Define short hands for commonly used exceptions.
prolog_format.pl  -- Analyse format specifications
prolog_history.pl
prolog_history/1	Execute Action on the history.
prolog_jiti.pl
jiti_list/0	List the JITI (Just In Time Indexes) of selected predicates.
jiti_list/1	List the JITI (Just In Time Indexes) of selected predicates.
jiti_suggest_modes/0	Propose modes for the predicates referenced by Spec.
jiti_suggest_modes/1	Propose modes for the predicates referenced by Spec.
prolog_metainference.pl
infer_meta_predicate/2	True when MetaSpec is a meta-predicate specifier for the predicate Head.
inferred_meta_predicate/2	True when MetaSpec is an inferred meta-predicate specification for Head.
prolog_pack.pl  -- A package manager for Prolog
prolog_profile.pl  -- Execution profiler
prolog_source.pl  -- Examine Prolog source-files
prolog_stack.pl
backtrace/1	Get and print a stacktrace to the user_error stream.
get_prolog_backtrace/2	Obtain a backtrace from the current location.
get_prolog_backtrace/3	Obtain a backtrace from the current location.
print_last_choicepoint/0	Print details on the last open choice point.
print_last_choicepoint/2
print_prolog_backtrace/2	Print a stacktrace in human readable form to Stream.
print_prolog_backtrace/3	Print a stacktrace in human readable form to Stream.
prolog_stack_frame_property/2	True when Property is a property of Frame.
stack_guard/1	Dynamic multifile hook that is normally not defined.
stack_guard/1	Dynamic multifile predicate.
prolog_trace.pl
list_tracing/0	List predicates we are currently tracing.
notraceall/0	Remove all trace points.
trace/1	Print passes through ports of specified predicates.
trace/2	Print passes through ports of specified predicates.
tracing/2	True if Spec is traced using Ports.
prolog_versions.pl  -- Demand specific (Prolog) versions
cmp_versions/3	Compare to versions.
require_prolog_version/2	Claim that the running Prolog version is at least version Required and provides the requested Features.
require_version/3	Require Component to have version CmpRequired, while Component is know to have version Available.
prolog_wrap.pl
current_predicate_wrapper/4	True if Head is wrapped with Body.
unwrap_predicate/2	Remove the outermost wrapper whose name unifies with Name.
wrap_predicate/4	Wrap the predicate referenced by Head using Body.
prolog_xref.pl  -- Prolog cross-referencer data collection
pure_input.pl  -- Pure Input from files and streams
qsave.pl  -- Save current program as a state or executable
quasi_quotations.pl  -- Define Quasi Quotation syntax
quintus.pl  -- Quintus compatibility
random.pl  -- Random numbers
rbtrees.pl  -- Red black trees
readln.pl
readutil.pl  -- Read utilities
record.pl  -- Access compound arguments by name
rwlocks.pl
with_rwlock/3	Run Goal, synchronized with LockId in ModeSpec.
with_rwlock/4	Run Goal, synchronized with LockId in ModeSpec.
sandbox.pl
sandbox_allowed_directive/1	Throws an exception if G is not considered a safe directive.
sandbox_allowed_expansion/1	Throws an exception if G is not considered a safe expansion goal.
sandbox_allowed_goal/1	Throw an exception if it is not safe to call G.
format_calls/3	Find ~@ calls from Format and Args.
safe_call/1	Call Goal if it complies with the sandboxing rules.
safe_directive/1	Hook to declare additional directives as safe.
safe_global_variable/1	Declare the given global variable safe to write to.
safe_goal/1	True if calling Goal provides no security risc.
safe_meta/2	Hook.
safe_primitive/1	True if Goal is safe to call (i.e., cannot access dangerous system-resources and cannot upset other parts of the Prolog process).
safe_prolog_flag/2	True if it is safe to set the flag Flag to Value.
settings.pl  -- Setting management
shell.pl
cd/0	Change working directory.
cd/1	Change working directory.
dirs/0	Manage the directory stack:.
file_style/2	True when File should be listed as a terminal hyperlink.
ls/0	Listing similar to Unix =ls -F=, flagging directories with =/=.
ls/1	Listing similar to Unix =ls -F=, flagging directories with =/=.
mv/2	Move (Rename) a file.
popd/0	Manage the directory stack:.
pushd/0	Manage the directory stack:.
pushd/1	Manage the directory stack:.
pwd/0	Print current working directory.
rm/1	Remove (unlink) a file.
shell/0	Execute an interactive shell.
shlib.pl  -- Utility library for loading foreign objects (DLLs, shared objects)
solution_sequences.pl  -- Modify solution sequences
sort.pl
statistics.pl  -- Get information about resource usage
streams.pl  -- Manage Prolog streams
strings.pl
dedent_lines/3	Remove shared indentation for all lines in a string.
indent_lines/3	Add Prefix to the beginning of lines in In.
indent_lines/4	Similar to indent_lines/3, but only adds Prefix to lines for which call(Filter, Line) succeeds.
interpolate_string/4	Establish a string from a template by replacing patterns.
string/4	Implements the quasi quotation syntax string.
string_lines/2	True when String represents Lines.
system.pl
lock_predicate/1	Transform a predicate into a system predicate.
system_mode/1	Switch the system into system or user mode.
system_module/0	Any predicate defined after this declaraction uptil the end of the file will become a system predicate.
unlock_predicate/1	Transform a system predicate into a normal system predicate.
tables.pl  -- XSB interface to tables
terms.pl  -- Term manipulation
thread.pl  -- High level thread primitives
call_in_thread/2	Run Goal as an interrupt in the context of Thread.
concurrent/3	Run Goals in parallel using N threads.
concurrent_and/2	Concurrent version of (Generator,Test).
concurrent_and/3	Concurrent version of (Generator,Test).
concurrent_forall/2	True when Action is true for all solutions of Generate.
concurrent_forall/3	True when Action is true for all solutions of Generate.
concurrent_maplist/2	Concurrent version of maplist/2.
concurrent_maplist/3	Concurrent version of maplist/2.
concurrent_maplist/4	Concurrent version of maplist/2.
first_solution/3	Try alternative solvers concurrently, returning the first answer.
thread_pool.pl  -- Resource bounded thread management
threadutil.pl  -- Interactive thread utilities
attach_console/0	Create a new console and make the standard Prolog streams point to it.
attach_console/1	Create a new console and make the standard Prolog streams point to it.
join_threads/0	Join all terminated threads.
tbacktrace/1	Print a backtrace for Thread to the stream user_error of the calling thread.
tbacktrace/2	Print a backtrace for Thread to the stream user_error of the calling thread.
tdebug/0	Enable debug-mode, trapping the graphical debugger on reaching spy-points or errors.
tdebug/1	Enable debug-mode, trapping the graphical debugger on reaching spy-points or errors.
thread_has_console/0	True when the calling thread has an attached console.
threads/0	List currently known threads with their status.
tnodebug/0	Disable debug-mode in all threads or the specified Thread.
tnodebug/1	Disable debug-mode in all threads or the specified Thread.
tprofile/1	Profile the operation of Thread until the user hits a key.
tspy/1	Trap the graphical debugger on reaching Spec in the specified or any thread.
tspy/2	Trap the graphical debugger on reaching Spec in the specified or any thread.
with_stopped_threads/2	Stop all threads except the caller while running once(Goal).
tty.pl
menu/3	Show a menu.
tty_clear/0	Clear the display.
tty_flash/0	Give visual signal if possible, otherwise beep.
ugraphs.pl  -- Graph manipulation library
url.pl  -- Analysing and constructing URL
utf8.pl  -- UTF-8 encoding/decoding on lists of character codes.
varnumbers.pl  -- Utilities for numbered terms
wfs.pl  -- Well Founded Semantics interface
when.pl  -- Conditional coroutining
writef.pl  -- Old-style formatted write
www_browser.pl  -- Open a URL in the users browser
yall.pl  -- Lambda expressions
zip.pl  -- Access resource ZIP archives