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  -- Extensible arithmetic
assoc.pl  -- Binary associations
atom.pl
identifier_parts/2	Parts is a list of atoms that make up Identifier.
join_identifier_parts/3	Join parts of an identifier according to Style.
restyle_identifier/3	Restyle an identifier by extracting the alnum substrings and joining them together according to Style.
backcomp.pl
$apropos_match/2	True if Needle is a sub atom of Haystack.
$arch/2
$argv/1
$declare_module/3	Used in triple20 particle library.
$home/1
$module/2
$set_prompt/1	Set the prompt for the toplevel.
$sig_atomic/1	Execute Goal without processing signals.
$strip_module/3	This used to be an internal predicate.
$version/1
C/3	Used to be generated by DCG.
at_initialization/1	Register goal only to be run if a saved state is restored.
call_cleanup/3	Call Cleanup with an indication of the reason unified to Catcher.
checklist/2
concat/3
concat_atom/2	Concatenate a list of atomic values to an atom.
concat_atom/3	Concatenate a list of atomic values to an atom, inserting Separator between each consecutive elements.
convert_time/2	Convert a time-stamp as obtained though get_time/1 into a textual representation using the C-library function ctime().
convert_time/8	Convert a time stamp, provided by get_time/1, time_file/2, etc.
current_module/2	True if Module is a module loaded from File.
current_mutex/3
current_thread/2
displayq/1	Write term ignoring operators and quote atoms.
displayq/2	Write term ignoring operators and quote atoms.
eval_license/0
export_list/2	Module exports the predicates of List.
feature/2	Control Prolog flags.
flush/0
free_variables/2	Return a list of unbound variables in Term.
hash/1	Demands PredInd to be indexed using a hash-table.
hash_term/2	If Term is ground, Hash is unified to an integer representing a hash for Term.
index/1	Prepare the predicate indicated by Head for multi-argument indexing.
lock_predicate/2
merge/3	Merge the ordered sets List1 and List2 into a new ordered list.
merge_set/3	Merge the ordered sets Set1 and Set2 into a new ordered set without duplicates.
message_queue_size/2	True if Queue holds Size terms.
proper_list/1	Old SWI-Prolog predicate to check for a list that really ends in a [].
read_clause/1
read_clause/2
read_history/6
read_pending_input/3
read_variables/2
read_variables/3
set_base_module/1	Set the default module from which we inherit.
set_feature/2	Control Prolog flags.
setup_and_call_cleanup/3	Call Cleanup once after Goal is finished.
setup_and_call_cleanup/4	Call Cleanup once after Goal is finished, with Catcher unified to the reason.
sformat/2
sformat/3
string_to_atom/2	Bi-directional conversion between string and atom.
string_to_list/2	Bi-directional conversion between a string and a list of character codes.
sublist/3	Succeeds if List2 unifies with a list holding those terms for which call(Goal, Elem) succeeds.
substring/4	Predecessor of sub_string using 1-based Offset.
sumlist/2	True when Sum is the list of all numbers in List.
thread_at_exit/1	Register Goal to be called when the calling thread exits.
trie_insert_new/3
unlock_predicate/2
write_ln/1
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  -- I/O on Lists of Character Codes
coinduction.pl  -- Co-Logic Programming
csv.pl  -- Process CSV (Comma-Separated Values) data
ctypes.pl  -- Character code classification
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
date_time_value/3	Extract values from a date-time structure.
day_of_the_week/2	Computes the day of the week for a given date.
day_of_the_year/2	Computes the day of the year for a given date.
parse_time/2	Stamp is a timestamp created from parsing Text using the representation Format.
parse_time/3	Stamp is a timestamp created from parsing Text using the representation Format.
debug.pl  -- Print debug messages and test assertions
dialect.pl  -- Support multiple Prolog dialects
dicts.pl  -- Dict utilities
dif.pl  -- The dif/2 constraint
edinburgh.pl
debug/0	Switch on/off debug mode.
display/1	Write a term, ignoring operators and special syntax constructs such as brace terms ({a}) and lists ([a,b,c]).
display/2	Write a term, ignoring operators and special syntax constructs such as brace terms ({a}) and lists ([a,b,c]).
fileerrors/2	Query and change the fileerrors flag.
nodebug/0	Switch on/off debug mode.
reconsult/1	Load source file(s), wiping the old content first.
unknown/2	Edinburgh Prolog predicate for dealing dealing with undefined procedures.
edit.pl  -- Editor interface
error.pl
exceptions.pl
catch/4	As catch/3, only catching exceptions for which exception(ErrorType,Ball) is true.
error_term/2	Describe the formal part of error(Formal,ImplDefined) exceptions.
exception/2	If Ball is unbound, adds a delayed goal that tests the error belongs to Type when Ball is instantiated (by catch/3).
exception_term/2	Describe exceptions that are not error(Formal, _) terms.
exception_type/2	Declare all exceptions subsumed by Term to be an exception of Type.
explain.pl  -- Describe Prolog Terms
fastrw.pl  -- Fast reading and writing of terms
files.pl
can_open_file/2	Succeeds if the user has access to `File' in mode `Mode'.
chdir/1	Change Working Directory.
gensym.pl  -- Generate unique symbols
git.pl  -- Run GIT commands
hashtable.pl
ht_del/3	Delete Key-Value from HT.
ht_gen/3	True when Key-Value is in HT.
ht_get/3	True when Key is in HT and associated with Value.
ht_is_hashtable/1	True when HT is a hash table.
ht_keys/2	True when Keys is an ordered set of all keys in HT.
ht_new/1	Create a new hash table.
ht_pairs/2	True when Pairs and HT represent the same association.
ht_put/3	Add a Key-Value to HT.
ht_put/5	Add Key-Value to HT.
ht_put_new/3	As ht_put/3, but fails if Key is already in HT instead of updating the associated value.
ht_size/2	True when Size is the number of key-value pairs in HT.
ht_update/4	True when HT holds Key-Old before and Key-New after this call.
heaps.pl
add_to_heap/4	Adds Key with priority Priority to Heap0, constructing a new heap in Heap.
delete_from_heap/4	Deletes Key from Heap0, leaving its priority in Priority and the resulting data structure in Heap.
empty_heap/1	True if Heap is an empty heap.
get_from_heap/4	Retrieves the minimum-priority pair Priority-Key from Heap0.
heap_size/2	Determines the number of elements in Heap.
heap_to_list/2	Constructs a list List of Priority-Element terms, ordered by (ascending) priority.
is_heap/1	Returns true if X is a heap.
list_to_heap/2	If List is a list of Priority-Element terms, constructs a heap out of List.
merge_heaps/3	Merge the two heaps Heap0 and Heap1 in Heap.
min_of_heap/3	Unifies Key with the minimum-priority element of Heap and Priority with its priority value.
min_of_heap/5	Gets the two minimum-priority elements from Heap.
singleton_heap/3	True if Heap is a heap with the single element Priority-Key.
help.pl  -- Text based manual
increval.pl  -- Incremental dynamic predicate modification
intercept.pl  -- Intercept and signal interface
iostream.pl  -- Utilities to deal with streams
lazy_lists.pl  -- Lazy list handling
listing.pl  -- List programs and pretty print clauses
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  -- Macro expansion
main.pl  -- Provide entry point for scripts
make.pl  -- Reload modified source files
modules.pl  -- Module utility predicates
nb_set.pl  -- Non-backtrackable sets
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  -- Option list processing
optparse.pl  -- command line parsing
ordsets.pl  -- Ordered set manipulation
oset.pl  -- Ordered set manipulation
pairs.pl  -- Operations on key-value lists
persistency.pl  -- Provide persistent dynamic predicates
pio.pl  -- Pure I/O
portray_text.pl  -- Portray text
pprint.pl
print_term/2	Pretty print a Prolog term.
predicate_options.pl  -- Access and analyse predicate options
prolog_autoload.pl  -- Autoload all dependencies
prolog_breakpoints.pl  -- Manage Prolog break-points
prolog_clause.pl
prolog_code.pl  -- Utilities for reasoning about code
prolog_codewalk.pl  -- Prolog code walker
prolog_colour.pl  -- Prolog syntax colouring support.
prolog_config.pl  -- Provide configuration information
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  -- Per-directory persistent commandline history
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  -- Print access to predicates
prolog_versions.pl  -- Demand specific (Prolog) versions
prolog_wrap.pl  -- Wrapping predicates
prolog_xref.pl
called_by/2	If this succeeds, the cross-referencer assumes Goal may call any of the goals in ListOfCalled.
called_by/4	True when Called is a list of callable terms called from Goal, handled by the predicate Module:Goal and executed in the context of the module Context.
hook/1	True if Goal is a hook that is called spontaneously (e.g., from foreign code).
meta_goal/2	Define meta-predicates.
xref_called/3	True when By is called from Called in Source.
xref_called/4	True when By is called from Called in Source.
xref_called/5	True when By is called from Called in Source.
xref_clean/1	Reset the database for the given source.
xref_comment/3	Is true when Source has a section comment with Title and Comment.
xref_comment/4	Is true when Head in Source has the given PlDoc comment.
xref_current_source/1	Check what sources have been analysed.
xref_defined/3	Test if Goal is accessible in Source.
xref_definition_line/2	If the 3th argument of xref_defined contains line info, return this in Line.
xref_done/2	Cross-reference executed at Time.
xref_exported/2	True when Source exports Head.
xref_hook/1	Definition of known hooks.
xref_meta/2	True when Called is a list of terms called from Head.
xref_meta/3	True when Head calls Called in Source.
xref_mode/3	Is true when Source provides a predicate with Mode and determinism.
xref_module/2	True if Module is defined in Source.
xref_op/2	Give the operators active inside the module.
xref_option/2	True when Source was processed using Option.
xref_prolog_flag/4	True when Flag is set to Value at Line in Source.
xref_public_list/3	Find meta-information about File.
xref_public_list/4	Find meta-information about File.
xref_public_list/6	Find meta-information about File.
xref_public_list/7	Find meta-information about File.
xref_source/1	Generate the cross-reference data for Source if not already done and the source is not modified.
xref_source/2	Generate the cross-reference data for Source if not already done and the source is not modified.
xref_source_file/3	Find named source file from Spec, relative to Src.
xref_source_file/4	Find named source file from Spec, relative to Src.
xref_uses_file/3	True when Source tries to load a file using Spec.
pure_input.pl  -- Pure Input from files and streams
qsave.pl
arch_shlib/3	This is a user defined hook called by qsave_program/2.
qsave_program/1	Make a saved state in file `File'.
qsave_program/2	Make a saved state in file `File'.
qsave_toplevel/0	Called to handle `-c file` compilaton.
quasi_quotations.pl  -- Define Quasi Quotation syntax
quintus.pl
abs/2	Unify `Absolute' with the absolute value of `Number'.
acos/2	Math library predicates.
asin/2	Math library predicates.
atan/2	Math library predicates.
atan2/3	Math library predicates.
atom_char/2	Same as ISO char_code/2.
ceiling/2	Math library predicates.
compile/1	Compile files.
cos/2	Math library predicates.
current_stream/3	SICStus/Quintus and backward compatible predicate.
date/1	Get current date as date(Y,M,D).
floor/2	Math library predicates.
genarg/3	Generalised version of ISO arg/3.
log/2	Math library predicates.
log10/2	Math library predicates.
midstring/3	Too difficult to explain.
midstring/4	Too difficult to explain.
midstring/5	Too difficult to explain.
midstring/6	Too difficult to explain.
no_style_check/1	Same as SWI-Prolog style_check(-Style).
on_exception/3
otherwise/0	For (A -> B ; otherwise -> C).
pow/3	Math library predicates.
prolog_flag/2	Same as ISO current_prolog_flag/2.
raise_exception/1	Quintus compatible exception handling.
round/2	Math library predicates.
sign/2	Math library predicates.
simple/1	Term is atomic or a variable.
sin/2	Math library predicates.
skip_line/0	Skip the rest of the current line (on Stream).
skip_line/1	Skip the rest of the current line (on Stream).
sqrt/2	Math library predicates.
stream_position/3	True when Old is the current position in Stream and the stream has been repositioned to New.
tan/2	Math library predicates.
unix/1	This predicate provides a partial emulation of the corresponding Quintus predicate.
random.pl  -- Random numbers
rbtrees.pl  -- Red black trees
readln.pl
readutil.pl  -- Read utilities
record.pl  -- Access compound arguments by name
rwlocks.pl  -- Read/write locks
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  -- Elementary shell commands
shlib.pl
compat_arch/2	User definable hook to establish if Arch1 is compatible with Arch2 when running a shared object.
current_foreign_library/2	Query currently loaded shared libraries.
load_foreign_library/1	Load a shared object or DLL.
load_foreign_library/2	Load a shared object or DLL.
reload_foreign_libraries/0	Reload all foreign libraries loaded (after restore of a state created using qsave_program/2.
unload_foreign_library/1	Unload a shared object or DLL.
unload_foreign_library/2	Unload a shared object or DLL.
use_foreign_library/1	Load and install a foreign library as load_foreign_library/1,2 and register the installation using initialization/2 with the option now.
use_foreign_library/2	Load and install a foreign library as load_foreign_library/1,2 and register the installation using initialization/2 with the option now.
solution_sequences.pl
call_nth/2	True when Goal succeeded for the Nth time.
distinct/1	True if Goal is true and no previous solution of Goal bound Witness to the same value.
distinct/2	True if Goal is true and no previous solution of Goal bound Witness to the same value.
group_by/4	Group bindings of Template that have the same value for By.
limit/2	Limit the number of solutions.
offset/2	Ignore the first Count solutions.
order_by/2	Order solutions according to Spec.
reduced/1	Similar to distinct/1, but does not guarantee unique results in return for using a limited amount of memory.
reduced/3	Similar to distinct/1, but does not guarantee unique results in return for using a limited amount of memory.
sort.pl
statistics.pl  -- Get information about resource usage
streams.pl  -- Manage Prolog streams
strings.pl  -- String utilities
system.pl  -- System utilities
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  -- Terminal operations
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
swritef/2	Use writef/1 or writef/2 and write the result to a string.
swritef/3	Use writef/1 or writef/2 and write the result to a string.
writef/1	Formatted write to the current_output.
writef/2	Formatted write to the current_output.
www_browser.pl
expand_url_path/2	Expand URL specifications similar to absolute_file_name/3.
known_browser/2	True if browser FileBaseName has a remote protocol compatible to Compatible.
www_open_url/1	Open URL in running version of the users' browser or start a new browser.
yall.pl  -- Lambda expressions
zip.pl  -- Access resource ZIP archives