E.1 Predicates

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

!/0	Cut (discard choicepoints)
!/1	Cut block. See block/3
,/2	Conjunction of goals
->/2	If-then-else
*->/2	Soft-cut
./2	Consult. Also list constructor
;/2	Disjunction of goals. Same as |/2
</2	Arithmetic smaller
=/2	Unification
=../2	``Univ.'' Term to list conversion
=:=/2	Arithmetic equal
=</2	Arithmetic smaller or equal
==/2	Identical
=@=/2	Structural identical
=\=/2	Arithmetic not equal
>/2	Arithmetic larger
>=/2	Arithmetic larger or equal
@</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	Not unifyable
\==/2	Not identical
\=@=/2	Not structural identical
^/2	Existential quantification (bagof/3, setof/3)
|/2	Disjunction of goals. Same as ;/2
abolish/1	Remove predicate definition from the database
abolish/2	Remove predicate definition from the database
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
access_file/2	Check access permissions of a file
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
arithmetic_function/1	Register an evaluable function
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)
assertz/1	Add a clause to the database (last)
assertz/2	Add a clause to the database (last)
assume/1	Make assertions about your program
attach_console/0	Attach I/O console to thread
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
at_initialization/1	Register goal to run at start-up
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_length/2	Determine length of an atom
atom_prefix/2	Test for start of atom
atom_number/2	Convert between atom and number
atom_to_term/3	Convert between atom and term
atomic/1	Type check for primitive
autoload/0	Autoload all predicates now
bagof/3	Find all solutions to a goal
between/3	Integer range checking/generating
block/3	Start a block (`catch'/`throw')
break/0	Start interactive toplevel
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_shared_object_function/2	UNIX: Call C-function in shared (.so) file
call_with_depth_limit/3	Prove goal with bounded depth
callable/1	Test for atom or compound term
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
checklist/2	Invoke goal on all members of a list
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)
compare/3	Compare, using a predicate to determine the order
compile_predicates/1	Compile dynamoc code to static
compiling/0	Is this a compilation run?
compound/1	Test for compound term
atom_concat/3	Append two atoms
code_type/2	Classify a character-code
concat_atom/2	Append a list of atoms
concat_atom/3	Append a list of atoms with separator
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_term/2	Make a copy of a term
current_arithmetic_function/1	Examine evaluable functions
current_atom/1	Examine existing atoms
current_char_conversion/2	Query input character mapping
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_module/1	Examine existing modules
current_module/2	Examine existing modules
current_mutex/3	Examine existing mutexes
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_thread/2	Examine Prolog threads
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	Get the default modules of a module
delete_directory/1	Remove a folder from the file system
delete_file/1	Remove a file from the file system
deterministic/1	Test deterministicy of current clause
discontiguous/1	Indicate distributed definition of a predicate
downcase_atom/2	Convert atom to lower-case
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
edit/0	Edit current script- or associated file
edit/1	Edit a file, predicate, module (extensible)
ensure_loaded/1	Consult a file if that has not yet been done
erase/1	Erase a database record or clause
eval_license/0	Evaluate licenses of loaded modules
exception/3	(hook) Handle runtime exceptions
exists_directory/1	Check existence of directory
exists_file/1	Check existence of file
exit/2	Exit from named block. See block/3
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_query/4	Expanded entered query
expand_term/2	Compiler: expand read term into clause(s)
explain/1	library(explain) Explain argument
explain/2	library(explain) 2nd argument is explanation of first
export/1	Export a predicate from a module
export_list/2	List of public predicates of a module
fail/0	Always false
fail/1	Immediately fail named block. See block/3
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
fileerrors/2	Do/Don't warn on file errors
findall/3	Find all solutions to a goal
flag/3	Simple global variable system
float/1	Type check for a floating point number
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_predicate/2	Program format/[1,2]
free_variables/2	Find unbound variables in a term
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
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
get0/1	Read next character
get0/2	Read next character from a stream
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_single_char/1	Read next character from the terminal
get_time/1	Get current time
getenv/2	Get shell environment variable
goal_expansion/2	Hook for macro-expanding goals
ground/1	Verify term holds no unbound variables
guitracer/0	Install hooks for the graphical debugger
halt/0	Exit from Prolog
halt/1	Exit from Prolog with status
hash_term/2	Hash-value of ground term
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
ignore/1	Call the argument, but always succeed
import/1	Import a predicate from a module
include/1	Include a file with declarations
index/1	Change clause indexing
initialization/1	Initialization directive
int_to_atom/2	Convert from integer to atom
int_to_atom/3	Convert from integer to atom (non-decimal)
integer/1	Type check for integer
interactor/0	Start new thread with console and toplevel
is/2	Evaluate arithmetic expression
is_absolute_file_name/1	True if arg defines an absolute path
is_list/1	Type check for a list
keysort/2	Sort, using a key
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/1	Define license for current file
license/2	Define license for named module
limit_stack/2	Limit stack expansion
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
listing/0	List program in current module
listing/1	List predicate
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)
make/0	Reconsult all changed source files
make_directory/1	Create a folder on the file system
make_fat_filemap/1	Win32: Create file containing non-FAT filenames
make_library_index/1	Create autoload file INDEX.pl
make_library_index/2	Create selective autoload file INDEX.pl
maplist/3	Transform all elements of a list
memberchk/2	Deterministic member/2
merge/3	Merge two sorted lists
merge_set/3	Merge two sorted sets
message_hook/3	Intercept print_message/2
message_queue_create/1	Create queue for thread communication
message_queue_destroy/1	Destroy queue for thread communication
message_to_string/2	Translate message-term to string
meta_predicate/1	Quintus compatibility
module/1	Query/set current type-in module
module/2	Declare 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_destroy/1	Destroy a mutex
mutex_lock/1	Become owner of a mutex
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
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
nonvar/1	Type check for bound term
noprotocol/0	Disable logging of user interaction
nospy/1	Remove spy point
nospyall/0	Remove all spy points
not/1	Negation by failure (argument not provable). Same as \+/1
notrace/0	Stop tracing
notrace/1	Do not debug argument goal
nth_clause/3	N-th clause of a predicate
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
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)
pce_dispatch/1	Run XPCE GUI in seperate 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
phrase/2	Activate grammar-rule set
phrase/3	Activate grammar-rule set (returning rest)
please/3	Query/change environment parameters
plus/3	Logical integer addition
portray/1	(hook) Modify behaviour of print/1
portray_clause/1	Pretty print a clause
portray_clause/2	Pretty print a clause to a stream
predicate_property/2	Query predicate attributes
predsort/3	Sort, using a predicate to determine the order
preprocessor/2	Install a preprocessor before the compiler
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/3	Obtain execution statistics
profile_count/3	Obtain profile results on a predicate
profiler/2	Obtain/change status of the profiler
prolog/0	Run interactive toplevel
prolog_choice_attribute/3	Examine the choice-point stack
prolog_current_frame/1	Reference to goal's environment stack
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_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 enviroment
prolog_list_goal/1	(hook) Intercept tracer 'L' command
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_to_os_filename/2	Convert between Prolog and OS filenames
prolog_trace_interception/4	library(user) Intercept the Prolog tracer
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
put/1	Write a character
put/2	Write a character on a stream
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
qcompile/1	Compile source to Quick Load File
qsave_program/1	Create runtime application
qsave_program/2	Create runtime application
read/1	Read Prolog term
read/2	Read Prolog term from stream
read_clause/1	Read clause
read_clause/2	Read clause from stream
read_history/6	Read using history substitution
read_link/3	Read a symbolic link
read_term/2	Read term with options
read_term/3	Read term with options from stream
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
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_profiler/0	Clear statistics obtained by the profiler
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
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
set_input/1	Set current input stream from a stream
set_output/1	Set current output stream from a stream
set_prolog_flag/2	Define a system feature
set_stream/2	Set stream attribute
set_stream_position/2	Seek stream to position
set_tty/2	Set `tty' stream
setarg/3	Destructive assignment on term
setenv/2	Set shell environment variable
setof/3	Find all unique solutions to a goal
sformat/2	Format on a string
sformat/3	Format on a string
shell/0	Execute interactive subshell
shell/1	Execute OS command
shell/2	Execute OS command
show_profile/1	Show results of the profiler
show_profile/2	Show results of the profiler
size_file/2	Get size of a file in characters
skip/1	Skip to character in current input
skip/2	Skip to character on stream
rl_add_history/1	Add line to readline(3) history
rl_read_init_file/1	Read readline(3) initTR>