F.1 Predicates

The predicate summary is used by the Prolog predicate apropos/1 to suggest predicates from a keyword.

@/2	Call using calling context
!/0	Cut (discard choicepoints)
,/2	Conjunction of goals
->/2	If-then-else
*->/2	Soft-cut
./2	Consult. Also functional notation
:</2	Select keys from a dict
;/2	Disjunction of two goals
</2	Arithmetic smaller
=/2	True when arguments are unified
=../2	“Univ.'' Term to list conversion
=:=/2	Arithmetic equality
=</2	Arithmetic smaller or equal
==/2	Test for strict equality
=@=/2	Test for structural equality (variant)
=\=/2	Arithmetic not equal
>/2	Arithmetic larger
>=/2	Arithmetic larger or equal
>:</2	Partial dict unification
?=/2	Test of terms can be compared now
@</2	Standard order smaller
@=</2	Standard order smaller or equal
@>/2	Standard order larger
@>=/2	Standard order larger or equal
\+/1	Negation by failure. Same as not/1
\=/2	True if arguments cannot be unified
\==/2	True if arguments are not strictly equal
\=@=/2	Not structural identical
^/2	Existential quantification (bagof/3, setof/3)
|/2	Disjunction in DCGs. Same as ;/2
/1	DCG escape; constraints
abolish/1	Remove predicate definition from the database
abolish/2	Remove predicate definition from the database
abolish_all_tables/0	Abolish computed tables
abolish_module_tables/1	Abolish all tables in a module
abolish_monotonic_tables/0	Abolish all monotonic tables
abolish_nonincremental_tables/0	Abolish non-auttomatic tables
abolish_nonincremental_tables/1	Abolish non-auttomatic tables
abolish_private_tables/0	Abolish tables of this thread
abolish_shared_tables/0	Abolish tables shared between threads
abolish_table_subgoals/1	Abolish tables for a goal
abort/0	Abort execution, return to top level
absolute_file_name/2	Get absolute path name
absolute_file_name/3	Get absolute path name with options
answer_count_restraint/0	Undefined answer due to max_answers
access_file/2	Check access permissions of a file
acyclic_term/1	Test term for cycles
add_import_module/3	Add module to the auto-import list
add_nb_set/2	Add term to a non-backtrackable set
add_nb_set/3	Add term to a non-backtrackable set
append/1	Append to a file
apply/2	Call goal with additional arguments
apropos/1	library(online_help) Search manual
arg/3	Access argument of a term
assoc_to_list/2	Convert association tree to list
assert/1	Add a clause to the database
assert/2	Add a clause to the database, give reference
asserta/1	Add a clause to the database (first)
asserta/2	Add a clause to the database (first)
assertion/1	Make assertions about your program
assertz/1	Add a clause to the database (last)
assertz/2	Add a clause to the database (last)
attach_console/0	Attach I/O console to thread
attach_packs/0	Attach add-ons
attach_packs/1	Attach add-ons from directory
attach_packs/2	Attach add-ons from directory
attribute_goals/3	Project attributes to goals
attr_unify_hook/2	Attributed variable unification hook
attr_portray_hook/2	Attributed variable print hook
attvar/1	Type test for attributed variable
at_end_of_stream/0	Test for end of file on input
at_end_of_stream/1	Test for end of file on stream
at_halt/1	Register goal to run at halt/1
atom/1	Type check for an atom
atom_chars/2	Convert between atom and list of characters
atom_codes/2	Convert between atom and list of characters codes
atom_concat/3	Contatenate two atoms
atom_length/2	Determine length of an atom
atom_number/2	Convert between atom and number
atom_prefix/2	Test for start of atom
atom_string/2	Conversion between atom and string
atom_to_term/3	Convert between atom and term
atomic/1	Type check for primitive
atomic_concat/3	Concatenate two atomic values to an atom
atomic_list_concat/2	Append a list of atomics
atomic_list_concat/3	Append a list of atomics with separator
atomics_to_string/2	Concatenate list of inputs to a string
atomics_to_string/3	Concatenate list of inputs to a string
autoload/1	Declare a file for autoloading
autoload/2	Declare a file for autoloading specific predicates
autoload_all/0	Autoload all predicates now
autoload_path/1	Add directories for autoloading
b_getval/2	Fetch backtrackable global variable
b_set_dict/3	Destructive assignment on a dict
b_setval/2	Assign backtrackable global variable
bagof/3	Find all solutions to a goal
between/3	Integer range checking/generating
blob/2	Type check for a blob
bounded_number/3	Number between bounds
break/0	Start interactive top level
break_hook/6	(hook) Debugger hook
byte_count/2	Byte-position in a stream
call/1	Call a goal
call/[2..]	Call with additional arguments
call_cleanup/3	Guard a goal with a cleaup-handler
call_cleanup/2	Guard a goal with a cleaup-handler
call_dcg/3	As phrase/3 without type checking
call_delays/2	Get the condition associated with an answer
call_residue_vars/2	Find residual attributed variables
call_residual_program/2	Get residual program associated with an answer
call_shared_object_function/2	UNIX: Call C-function in shared (.so) file
call_with_depth_limit/3	Prove goal with bounded depth
call_with_inference_limit/3	Prove goal in limited inferences
callable/1	Test for atom or compound term
cancel_halt/1	Cancel halt/0 from an at_halt/1 hook
catch/3	Call goal, watching for exceptions
char_code/2	Convert between character and character code
char_conversion/2	Provide mapping of input characters
char_type/2	Classify characters
character_count/2	Get character index on a stream
chdir/1	Compatibility: change working directory
chr_constraint/1	CHR Constraint declaration
chr_show_store/1	List suspended CHR constraints
chr_trace/0	Start CHR tracer
chr_type/1	CHR Type declaration
chr_notrace/0	Stop CHR tracer
chr_leash/1	Define CHR leashed ports
chr_option/2	Specify CHR compilation options
clause/2	Get clauses of a predicate
clause/3	Get clauses of a predicate
clause_property/2	Get properties of a clause
close/1	Close stream
close/2	Close stream (forced)
close_dde_conversation/1	Win32: Close DDE channel
close_shared_object/1	UNIX: Close shared library (.so file)
collation_key/2	Sort key for locale dependent ordering
comment_hook/3	(hook) handle comments in sources
compare/3	Compare, using a predicate to determine the order
compile_aux_clauses/1	Compile predicates for goal_expansion/2
compile_predicates/1	Compile dynamic code to static
compiling/0	Is this a compilation run?
compound/1	Test for compound term
compound_name_arity/3	Name and arity of a compound term
compound_name_arguments/3	Name and arguments of a compound term
code_type/2	Classify a character-code
consult/1	Read (compile) a Prolog source file
context_module/1	Get context module of current goal
convert_time/8	Break time stamp into fields
convert_time/2	Convert time stamp to string
copy_stream_data/2	Copy all data from stream to stream
copy_stream_data/3	Copy n bytes from stream to stream
copy_predicate_clauses/2	Copy clauses between predicates
copy_term/2	Make a copy of a term
copy_term/3	Copy a term and obtain attribute-goals
copy_term_nat/2	Make a copy of a term without attributes
create_prolog_flag/3	Create a new Prolog flag
current_arithmetic_function/1	Examine evaluable functions
current_atom/1	Examine existing atoms
current_blob/2	Examine typed blobs
current_char_conversion/2	Query input character mapping
current_engine/1	Enumerate known engines
current_flag/1	Examine existing flags
current_foreign_library/2	library(shlib) Examine loaded shared libraries (.so files)
current_format_predicate/2	Enumerate user-defined format codes
current_functor/2	Examine existing name/arity pairs
current_input/1	Get current input stream
current_key/1	Examine existing database keys
current_locale/1	Get the current locale
current_module/1	Examine existing modules
current_op/3	Examine current operator declarations
current_output/1	Get the current output stream
current_predicate/1	Examine existing predicates (ISO)
current_predicate/2	Examine existing predicates
current_signal/3	Current software signal mapping
current_stream/3	Examine open streams
current_table/2	Find answer table for a variant
current_transaction/1	Detect encapsulating transactions
current_trie/1	Enumerate known tries
cyclic_term/1	Test term for cycles
day_of_the_week/2	Determine ordinal-day from date
date_time_stamp/2	Convert date structure to time-stamp
date_time_value/3	Extract info from a date structure
dcg_translate_rule/2	Source translation of DCG rules
dcg_translate_rule/4	Source translation of DCG rules
dde_current_connection/2	Win32: Examine open DDE connections
dde_current_service/2	Win32: Examine DDE services provided
dde_execute/2	Win32: Execute command on DDE server
dde_register_service/2	Win32: Become a DDE server
dde_request/3	Win32: Make a DDE request
dde_poke/3	Win32: POKE operation on DDE server
dde_unregister_service/1	Win32: Terminate a DDE service
debug/0	Test for debugging mode
debug/1	Select topic for debugging
debug/3	Print debugging message on topic
debug_control_hook/1	(hook) Extend spy/1, etc.
debugging/0	Show debugger status
debugging/1	Test where we are debugging topic
default_module/2	Query module inheritance
del_attr/2	Delete attribute from variable
del_attrs/1	Delete all attributes from variable
del_dict/4	Delete Key-Value pair from a dict
delays_residual_program/2	Get the residual program for an answer
delete_directory/1	Remove a folder from the file system
delete_file/1	Remove a file from the file system
delete_import_module/2	Remove module from import list
deterministic/1	Test deterministicy of current clause
dif/2	Constrain two terms to be different
directory_files/2	Get entries of a directory/folder
discontiguous/1	Indicate distributed definition of a predicate
divmod/4	Compute quotient and remainder of two integers
downcase_atom/2	Convert atom to lower-case
duplicate_term/2	Create a copy of a term
dwim_match/2	Atoms match in “Do What I Mean'' sense
dwim_match/3	Atoms match in “Do What I Mean'' sense
dwim_predicate/2	Find predicate in “Do What I Mean'' sense
dynamic/1	Indicate predicate definition may change
dynamic/2	Indicate predicate definition may change
edit/0	Edit current script- or associated file
edit/1	Edit a file, predicate, module (extensible)
elif/1	Part of conditional compilation (directive)
else/0	Part of conditional compilation (directive)
empty_assoc/1	Create/test empty association tree
empty_nb_set/1	Test/create an empty non-backtrackable set
encoding/1	Define encoding inside a source file
endif/0	End of conditional compilation (directive)
engine_create/3	Create an interactor
engine_create/4	Create an interactor
engine_destroy/1	Destroy an interactor
engine_fetch/1	Get term from caller
engine_next/2	Ask interactor for next term
engine_next_reified/2	Ask interactor for next term
engine_post/2	Send term to an interactor
engine_post/3	Send term to an interactor and wait for reply
engine_self/1	Get handle to running interactor
engine_yield/1	Make term available to caller
ensure_loaded/1	Consult a file if that has not yet been done
erase/1	Erase a database record or clause
exception/3	(hook) Handle runtime exceptions
exists_directory/1	Check existence of directory
exists_file/1	Check existence of file
exists_source/1	Check existence of a Prolog source
exists_source/2	Check existence of a Prolog source
expand_answer/2	Expand answer of query
expand_file_name/2	Wildcard expansion of file names
expand_file_search_path/2	Wildcard expansion of file paths
expand_goal/2	Compiler: expand goal in clause-body
expand_goal/4	Compiler: expand goal in clause-body
expand_query/4	Expanded entered query
expand_term/2	Compiler: expand read term into clause(s)
expand_term/4	Compiler: expand read term into clause(s)
expects_dialect/1	For which Prolog dialect is this code written?
explain/1	library(explain) Explain argument
explain/2	library(explain) 2nd argument is explanation of first
export/1	Export a predicate from a module
fail/0	Always false
false/0	Always false
fast_term_serialized/2	Fast term (de-)serialization
fast_read/2	Read binary term serialization
fast_write/2	Write binary term serialization
current_prolog_flag/2	Get system configuration parameters
file_base_name/2	Get file part of path
file_directory_name/2	Get directory part of path
file_name_extension/3	Add, remove or test file extensions
file_search_path/2	Define path-aliases for locating files
find_chr_constraint/1	Returns a constraint from the store
findall/3	Find all solutions to a goal
findall/4	Difference list version of findall/3
findnsols/4	Find first N solutions
findnsols/5	Difference list version of findnsols/4
fill_buffer/1	Fill the input buffer of a stream
flag/3	Simple global variable system
float/1	Type check for a floating point number
float_class/2	Classify (special) floats
float_parts/4	Get mantissa and exponent of a float
flush_output/0	Output pending characters on current stream
flush_output/1	Output pending characters on specified stream
forall/2	Prove goal for all solutions of another goal
format/1	Formatted output
format/2	Formatted output with arguments
format/3	Formatted output on a stream
format_time/3	C strftime() like date/time formatter
format_time/4	date/time formatter with explicit locale
format_predicate/2	Program format/[1,2]
term_attvars/2	Find attributed variables in a term
term_variables/2	Find unbound variables in a term
term_variables/3	Find unbound variables in a term
text_to_string/2	Convert arbitrary text to a string
freeze/2	Delay execution until variable is bound
frozen/2	Query delayed goals on var
functor/3	Get name and arity of a term or construct a term
garbage_collect/0	Invoke the garbage collector
garbage_collect_atoms/0	Invoke the atom garbage collector
garbage_collect_clauses/0	Invoke clause garbage collector
gen_assoc/3	Enumerate members of association tree
gen_nb_set/2	Generate members of non-backtrackable set
gensym/2	Generate unique atoms from a base
get/1	Read first non-blank character
get/2	Read first non-blank character from a stream
get_assoc/3	Fetch key from association tree
get_assoc/5	Fetch key from association tree
get_attr/3	Fetch named attribute from a variable
get_attrs/2	Fetch all attributes of a variable
get_byte/1	Read next byte (ISO)
get_byte/2	Read next byte from a stream (ISO)
get_char/1	Read next character as an atom (ISO)
get_char/2	Read next character from a stream (ISO)
get_code/1	Read next character (ISO)
get_code/2	Read next character from a stream (ISO)
get_dict/3	Get the value associated to a key from a dict
get_dict/5	Replace existing value in a dict
get_flag/2	Get value of a flag
get_single_char/1	Read next character from the terminal
get_string_code/3	Get character code at index in string
get_time/1	Get current time
get0/1	Read next character
get0/2	Read next character from a stream
getenv/2	Get shell environment variable
goal_expansion/2	Hook for macro-expanding goals
goal_expansion/4	Hook for macro-expanding goals
ground/1	Verify term holds no unbound variables
gdebug/0	Debug using graphical tracer
gspy/1	Spy using graphical tracer
gtrace/0	Trace using graphical tracer
guitracer/0	Install hooks for the graphical debugger
gxref/0	Cross-reference loaded program
halt/0	Exit from Prolog
halt/1	Exit from Prolog with status
term_hash/2	Hash-value of ground term
term_hash/4	Hash-value of term with depth limit
help/0	Give help on help
help/1	Give help on predicates and show parts of manual
help_hook/1	(hook) User-hook in the help-system
if/1	Start conditional compilation (directive)
ignore/1	Call the argument, but always succeed
import/1	Import a predicate from a module
import_module/2	Query import modules
in_pce_thread/1	Run goal in XPCE thread
in_pce_thread_sync/1	Run goal in XPCE thread
include/1	Include a file with declarations
initialization/1	Initialization directive
initialization/2	Initialization directive
initialize/0	Run program initialization
instance/2	Fetch clause or record from reference
integer/1	Type check for integer
interactor/0	Start new thread with console and top level
is/2	Evaluate arithmetic expression
is_absolute_file_name/1	True if arg defines an absolute path
is_assoc/1	Verify association list
is_dict/1	Type check for a dict
is_dict/2	Type check for a dict in a class
is_engine/1	Type check for an engine handle
is_list/1	Type check for a list
is_most_general_term/1	Type check for general term
is_stream/1	Type check for a stream handle
is_trie/1	Type check for a trie handle
is_thread/1	Type check for an thread handle
join_threads/0	Join all terminated threads interactively
keysort/2	Sort, using a key
known_licenses/0	Print known licenses
last/2	Last element of a list
leash/1	Change ports visited by the tracer
length/2	Length of a list
library_directory/1	(hook) Directories holding Prolog libraries
license/0	Evaluate licenses of loaded modules
license/1	Define license for current file
license/2	Define license for named module
line_count/2	Line number on stream
line_position/2	Character position in line on stream
list_debug_topics/0	List registered topics for debugging
list_to_assoc/2	Create association tree from list
list_to_set/2	Remove duplicates from a list
list_strings/0	Help porting to version 7
load_files/1	Load source files
load_files/2	Load source files with options
load_foreign_library/1	library(shlib) Load shared library (.so file)
load_foreign_library/2	library(shlib) Load shared library (.so file)
locale_create/3	Create a new locale object
locale_destroy/1	Destroy a locale object
locale_property/2	Query properties of locale objects
locale_sort/2	Language dependent sort of atoms
make/0	Reconsult all changed source files
make_directory/1	Create a folder on the file system
make_library_index/1	Create autoload file INDEX.pl
malloc_property/1	Property of the allocator
make_library_index/2	Create selective autoload file INDEX.pl
map_assoc/2	Map association tree
map_assoc/3	Map association tree
dict_create/3	Create a dict from data
dict_pairs/3	Convert between dict and list of pairs
max_assoc/3	Highest key in association tree
memberchk/2	Deterministic member/2
message_hook/3	Intercept print_message/2
message_line_element/2	(hook) Intercept print_message_lines/3
message_property/2	(hook) Define display of a message
message_queue_create/1	Create queue for thread communication
message_queue_create/2	Create queue for thread communication
message_queue_destroy/1	Destroy queue for thread communication
message_queue_property/2	Query message queue properties
message_queue_set/2	Set a message queue property
message_to_string/2	Translate message-term to string
meta_predicate/1	Declare access to other predicates
min_assoc/3	Lowest key in association tree
module/1	Query/set current type-in module
module/2	Declare a module
module/3	Declare a module with language options
module_property/2	Find properties of a module
module_transparent/1	Indicate module based meta-predicate
msort/2	Sort, do not remove duplicates
multifile/1	Indicate distributed definition of predicate
mutex_create/1	Create a thread-synchronisation device
mutex_create/2	Create a thread-synchronisation device
mutex_destroy/1	Destroy a mutex
mutex_lock/1	Become owner of a mutex
mutex_property/2	Query mutex properties
mutex_statistics/0	Print statistics on mutex usage
mutex_trylock/1	Become owner of a mutex (non-blocking)
mutex_unlock/1	Release ownership of mutex
mutex_unlock_all/0	Release ownership of all mutexes
name/2	Convert between atom and list of character codes
nb_current/2	Enumerate non-backtrackable global variables
nb_delete/1	Delete a non-backtrackable global variable
nb_getval/2	Fetch non-backtrackable global variable
nb_link_dict/3	Non-backtrackable assignment to dict
nb_linkarg/3	Non-backtrackable assignment to term
nb_linkval/2	Assign non-backtrackable global variable
nb_set_to_list/2	Convert non-backtrackable set to list
nb_set_dict/3	Non-backtrackable assignment to dict
nb_setarg/3	Non-backtrackable assignment to term
nb_setval/2	Assign non-backtrackable global variable
nl/0	Generate a newline
nl/1	Generate a newline on a stream
nodebug/0	Disable debugging
nodebug/1	Disable debug-topic
noguitracer/0	Disable the graphical debugger
nonground/2	Term is not ground due to witness
nonvar/1	Type check for bound term
nonterminal/1	Set predicate property
noprofile/1	Hide (meta-) predicate for the profiler
noprotocol/0	Disable logging of user interaction
normalize_space/2	Normalize white space
nospy/1	Remove spy point
nospyall/0	Remove all spy points
not/1	Negation by failure (argument not provable). Same as \+/1
not_exists/1	Tabled negation for non-ground or non-tabled goals
notrace/0	Stop tracing
notrace/1	Do not debug argument goal
nth_clause/3	N-th clause of a predicate
nth_integer_root_and_remainder/4	Integer root and remainder
number/1	Type check for integer or float
number_chars/2	Convert between number and one-char atoms
number_codes/2	Convert between number and character codes
number_string/2	Convert between number and string
numbervars/3	Number unbound variables of a term
numbervars/4	Number unbound variables of a term
on_signal/3	Handle a software signal
once/1	Call a goal deterministically
op/3	Declare an operator
open/3	Open a file (creating a stream)
open/4	Open a file (creating a stream)
open_dde_conversation/3	Win32: Open DDE channel
open_null_stream/1	Open a stream to discard output
open_resource/3	Open a program resource as a stream
open_shared_object/2	UNIX: Open shared library (.so file)
open_shared_object/3	UNIX: Open shared library (.so file)
open_source_hook/3	(hook) Open a source file
open_string/2	Open a string as a stream
ord_list_to_assoc/2	Convert ordered list to assoc
parse_time/2	Parse text to a time-stamp
parse_time/3	Parse text to a time-stamp
pce_dispatch/1	Run XPCE GUI in separate thread
pce_call/1	Run goal in XPCE GUI thread
peek_byte/1	Read byte without removing
peek_byte/2	Read byte without removing
peek_char/1	Read character without removing
peek_char/2	Read character without removing
peek_code/1	Read character-code without removing
peek_code/2	Read character-code without removing
peek_string/3	Read a string without removing
phrase/2	Activate grammar-rule set
phrase/3	Activate grammar-rule set (returning rest)
phrase_from_quasi_quotation/2	Parse quasi quotation with DCG
please/3	Query/change environment parameters
plus/3	Logical integer addition
portray/1	(hook) Modify behaviour of print/1
predicate_property/2	Query predicate attributes
predsort/3	Sort, using a predicate to determine the order
print/1	Print a term
print/2	Print a term on a stream
print_message/2	Print message from (exception) term
print_message_lines/3	Print message to stream
profile/1	Obtain execution statistics
profile/2	Obtain execution statistics
profile_count/3	Obtain profile results on a predicate
profiler/2	Obtain/change status of the profiler
prolog/0	Run interactive top level
prolog_alert_signal/2	Query/set unblock signal
prolog_choice_attribute/3	Examine the choice point stack
prolog_current_choice/1	Reference to most recent choice point
prolog_current_frame/1	Reference to goal's environment stack
prolog_cut_to/1	Realise global cuts
prolog_edit:locate/2	Locate targets for edit/1
prolog_edit:locate/3	Locate targets for edit/1
prolog_edit:edit_source/1	Call editor for edit/1
prolog_edit:edit_command/2	Specify editor activation
prolog_edit:load/0	Load edit/1 extensions
prolog_exception_hook/4	Rewrite exceptions
prolog_file_type/2	Define meaning of file extension
prolog_frame_attribute/3	Obtain information on a goal environment
prolog_ide/1	Program access to the development environment
prolog_list_goal/1	(hook) Intercept tracer’L' command
prolog_listen/2	Listen to Prolog events
prolog_listen/3	Listen to Prolog events
prolog_load_context/2	Context information for directives
prolog_load_file/2	(hook) Program load_files/2
prolog_skip_level/2	Indicate deepest recursion to trace
prolog_skip_frame/1	Perform‘skip' on a frame
prolog_stack_property/2	Query properties of the stacks
prolog_to_os_filename/2	Convert between Prolog and OS filenames
prolog_trace_interception/4	library(user) Intercept the Prolog tracer
prolog_unlisten/2	Stop listening to Prolog events
project_attributes/2	Project constraints to query variables
prompt1/1	Change prompt for 1 line
prompt/2	Change the prompt used by read/1
protocol/1	Make a log of the user interaction
protocola/1	Append log of the user interaction to file
protocolling/1	On what file is user interaction logged
public/1	Declaration that a predicate may be called
put/1	Write a character
put/2	Write a character on a stream
put_assoc/4	Add Key-Value to association tree
put_attr/3	Put attribute on a variable
put_attrs/2	Set/replace all attributes on a variable
put_byte/1	Write a byte
put_byte/2	Write a byte on a stream
put_char/1	Write a character
put_char/2	Write a character on a stream
put_code/1	Write a character-code
put_code/2	Write a character-code on a stream
put_dict/3	Add/replace multiple keys in a dict
put_dict/4	Add/replace a single key in a dict
qcompile/1	Compile source to Quick Load File
qcompile/2	Compile source to Quick Load File
qsave_program/1	Create runtime application
qsave_program/2	Create runtime application
quasi_quotation_syntax/1	Declare quasi quotation syntax
quasi_quotation_syntax_error/1	Raise syntax error
radial_restraint/0	Tabbling radial restraint was violated
random_property/1	Query properties of random generation
rational/1	Type check for a rational number
rational/3	Decompose a rational
read/1	Read Prolog term
read/2	Read Prolog term from stream
read_clause/3	Read clause from stream
read_link/3	Read a symbolic link
read_pending_codes/3	Fetch buffered input from a stream
read_pending_chars/3	Fetch buffered input from a stream
read_string/3	Read a number of characters into a string
read_string/5	Read string upto a delimiter
read_term/2	Read term with options
read_term/3	Read term with options from stream
read_term_from_atom/3	Read term with options from atom
read_term_with_history/2	Read term with command line history
recorda/2	Record term in the database (first)
recorda/3	Record term in the database (first)
recorded/2	Obtain term from the database
recorded/3	Obtain term from the database
recordz/2	Record term in the database (last)
recordz/3	Record term in the database (last)
redefine_system_predicate/1	Abolish system definition
reexport/1	Load files and re-export the imported predicates
reexport/2	Load predicates from a file and re-export it
reload_foreign_libraries/0	Reload DLLs/shared objects
reload_library_index/0	Force reloading the autoload index
rename_file/2	Change name of file
repeat/0	Succeed, leaving infinite backtrack points
require/1	This file requires these predicates
reset/3	Wrapper for delimited continuations
reset_gensym/1	Reset a gensym key
reset_gensym/0	Reset all gensym keys
reset_profiler/0	Clear statistics obtained by the profiler
resource/2	Declare a program resource
resource/3	Declare a program resource
retract/1	Remove clause from the database
retractall/1	Remove unifying clauses from the database
same_file/2	Succeeds if arguments refer to same file
same_term/2	Test terms to be at the same address
see/1	Change the current input stream
seeing/1	Query the current input stream
seek/4	Modify the current position in a stream
seen/0	Close the current input stream
select_dict/2	Select matching attributes from a dict
select_dict/3	Select matching attributes from a dict
set_end_of_stream/1	Set physical end of an open file
set_flag/2	Set value of a flag
set_input/1	Set current input stream from a stream
set_locale/1	Set the default local
set_malloc/1	Set memory allocator property
set_module/1	Set properties of a module
set_output/1	Set current output stream from a stream
set_prolog_IO/3	Prepare streams for interactive session
set_prolog_flag/2	Define a system feature
set_prolog_gc_thread/1	Control the gc thread
set_prolog_stack/2	Modify stack characteristics
set_random/1	Control random number generation
set_stream/2	Set stream attribute
set_stream_position/2	Seek stream to position
set_system_IO/3	Rebind stdin/stderr/stdout
setup_call_cleanup/3	Undo side-effects safely
setup_call_catcher_cleanup/4	Undo side-effects safely
setarg/3	Destructive assignment on term
setenv/2	Set shell environment variable
setlocale/3	Set/query C-library regional information
setof/3	Find all unique solutions to a goal
shell/1	Execute OS command
shell/2	Execute OS command
shift/1	Shift control to the closest reset/3
show_profile/1	Show results of the profiler
size_abstract_term/3	Abstract a term (tabling support)
size_file/2	Get size of a file in characters
size_nb_set/2	Determine size of non-backtrackable set
skip/1	Skip to character in current input
skip/2	Skip to character on stream
sleep/1	Suspend execution for specified time
snapshot/1	Run goal in isolation
sort/2	Sort elements in a list
sort/4	Sort elements in a list
source_exports/2	Check whether source exports a predicate
source_file/1	Examine currently loaded source files
source_file/2	Obtain source file of predicate
source_file_property/2	Information about loaded files
source_location/2	Location of last read term
split_string/4	Break a string into substrings
spy/1	Force tracer on specified predicate
stamp_date_time/3	Convert time-stamp to date structure
statistics/0	Show execution statistics
statistics/2	Obtain collected statistics
stream_pair/3	Create/examine a bi-directional stream
stream_position_data/3	Access fields from stream position
stream_property/2	Get stream properties
string/1	Type check for string
string_concat/3	atom_concat/3 for strings
string_length/2	Determine length of a string
string_chars/2	Conversion between string and list of characters
string_codes/2	Conversion between string and list of character codes
string_code/3	Get or find a character code in a string
string_lower/2	Case conversion to lower case
string_upper/2	Case conversion to upper case
string_predicate/1	(hook) Predicate contains strings
strip_module/3	Extract context module and term
style_check/1	Change level of warnings
sub_atom/5	Take a substring from an atom
sub_atom_icasechk/3	Case insensitive substring match
sub_string/5	Take a substring from a string
subsumes_term/2	One-sided unification test
succ/2	Logical integer successor relation
swritef/2	Formatted write on a string
swritef/3	Formatted write on a string
tab/1	Output number of spaces
tab/2	Output number of spaces on a stream
table/1	Declare predicate to be tabled
tabled_call/1	Helper for not_exists/1
tdebug/0	Switch all threads into debug mode
tdebug/1	Switch a thread into debug mode
tell/1	Change current output stream
telling/1	Query current output stream
term_expansion/2	(hook) Convert term before compilation
term_expansion/4	(hook) Convert term before compilation
term_singletons/2	Find singleton variables in a term
term_string/2	Read/write a term from/to a string
term_string/3	Read/write a term from/to a string
term_subsumer/3	Most specific generalization of two terms
term_to_atom/2	Convert between term and atom
thread_affinity/3	Query and control the affinity mask
thread_alias/1	Set the alias name of a thread
thread_at_exit/1	Register goal to be called at exit
thread_create/2	Create a new Prolog task
thread_create/3	Create a new Prolog task
thread_detach/1	Make thread cleanup after completion
thread_exit/1	Terminate Prolog task with value
thread_get_message/1	Wait for message
thread_get_message/2	Wait for message in a queue
thread_get_message/3	Wait for message in a queue
thread_idle/2	Reduce footprint while waiting
thread_initialization/1	Run action at start of thread
thread_join/1	Wait for Prolog task-completion
thread_join/2	Wait for Prolog task-completion
thread_local/1	Declare thread-specific clauses for a predicate
thread_message_hook/3	Thread local message_hook/3
thread_peek_message/1	Test for message
thread_peek_message/2	Test for message in a queue
thread_property/2	Examine Prolog threads
thread_self/1	Get identifier of current thread
thread_send_message/2	Send message to another thread
thread_send_message/3	Send message to another thread
thread_setconcurrency/2	Number of active threads
thread_signal/2	Execute goal in another thread
thread_statistics/3	Get statistics of another thread
thread_update/2	Update a module and signal waiters
thread_wait/2	Wait for a goal to become true
threads/0	List running threads
throw/1	Raise an exception (see catch/3)
time/1	Determine time needed to execute goal
time_file/2	Get last modification time of file
tmp_file/2	Create a temporary filename
tmp_file_stream/3	Create a temporary file and open it
tnodebug/0	Switch off debug mode in all threads
tnodebug/1	Switch off debug mode in a thread
tnot/1	Tabled negation
told/0	Close current output
tprofile/1	Profile a thread for some period
trace/0	Start the tracer
trace/1	Set trace point on predicate
trace/2	Set/Clear trace point on ports
tracing/0	Query status of the tracer
transaction/1	Run goal in a transaction
transaction/2	Run goal in a transaction
transaction/3	Run goal in a transaction
transaction_updates/1	Updates to be committed in a transaction
trie_delete/3	Remove term from trie
trie_destroy/1	Destroy a trie
trie_gen/3	Get all terms from a trie
trie_gen_compiled/2	Get all terms from a trie
trie_gen_compiled/3	Get all terms from a trie
trie_insert/2	Insert term into a trie
trie_insert/3	Insert term into a trie
trie_insert/4	Insert term into a trie
trie_lookup/3	Lookup a term in a trie
trie_new/1	Create a trie
trie_property/2	Examine a trie's properties
trie_update/3	Update associated value in trie
trie_term/2	Get term from a trie by handle
trim_stacks/0	Release unused memory resources
tripwire/2	(hook) Handle a tabling tripwire event
true/0	Succeed
tspy/1	Set spy point and enable debugging in all threads
tspy/2	Set spy point and enable debugging in a thread
tty_get_capability/3	Get terminal parameter
tty_goto/2	Goto position on screen
tty_put/2	Write control string to terminal
tty_size/2	Get row/column size of the terminal
ttyflush/0	Flush output on terminal
undefined/0	Well Founded Semantics: true nor false
unify_with_occurs_check/2	Logically sound unification
unifiable/3	Determining binding required for unification
unknown/2	Trap undefined predicates
unload_file/1	Unload a source file
unload_foreign_library/1	library(shlib) Detach shared library (.so file)
unload_foreign_library/2	library(shlib) Detach shared library (.so file)
unsetenv/1	Delete shell environment variable
untable/1	Remove tabling instrumentation
upcase_atom/2	Convert atom to upper-case
use_foreign_library/1	Load DLL/shared object (directive)
use_foreign_library/2	Load DLL/shared object (directive)
use_module/1	Import a module
use_module/2	Import predicates from a module
valid_string_goal/1	(hook) Goal handles strings
var/1	Type check for unbound variable
var_number/2	Check that var is numbered by numbervars
var_property/2	Variable properties during macro expansion
variant_sha1/2	Term-hash for term-variants
variant_hash/2	Term-hash for term-variants
version/0	Print system banner message
version/1	Add messages to the system banner
visible/1	Ports that are visible in the tracer
volatile/1	Predicates that are not saved
wait_for_input/3	Wait for input with optional timeout
when/2	Execute goal when condition becomes true
wildcard_match/2	POSIX style glob pattern matching
wildcard_match/3	POSIX style glob pattern matching
win_add_dll_directory/1	Add directory to DLL search path
win_add_dll_directory/2	Add directory to DLL search path
win_remove_dll_directory/1	Remove directory from DLL search path
win_exec/2	Win32: spawn Windows task
win_has_menu/0	Win32: true if console menu is available
win_folder/2	Win32: get special folder by CSIDL
win_insert_menu/2	swipl-win.exe: add menu
win_insert_menu_item/4	swipl-win.exe: add item to menu
win_shell/2	Win32: open document through Shell
win_shell/3	Win32: open document through Shell
win_registry_get_value/3	Win32: get registry value
win_window_color/2	Win32: change colors of console window
win_window_pos/1	Win32: change size and position of window
window_title/2	Win32: change title of window
with_mutex/2	Run goal while holding mutex
with_output_to/2	Write to strings and more
with_quasi_quotation_input/3	Parse quasi quotation from stream
with_tty_raw/1	Run goal with terminal in raw mode
working_directory/2	Query/change CWD
write/1	Write term
write/2	Write term to stream
writeln/1	Write term, followed by a newline
writeln/2	Write term, followed by a newline to a stream
write_canonical/1	Write a term with quotes, ignore operators
write_canonical/2	Write a term with quotes, ignore operators on a stream
write_length/3	Dermine #characters to output a term
write_term/2	Write term with options
write_term/3	Write term with options to stream
writef/1	Formatted write
writef/2	Formatted write on stream
writeq/1	Write term, insert quotes
writeq/2	Write term, insert quotes on stream