Event Types

C.1 Event Types

C.1.1 Argument Types and Values

Event	Event Type	Default Event Handler
1	general error	error_handler / 2
2	term of an unknown type	error_handler / 2
4	instantiation fault	error_handler / 4
5	type error	error_handler / 4
6	out of range	error_handler / 4
7	string contains unexpected characters	error_handler / 2
8	bad argument list	error_handler / 2

C.1.2 Arithmetic, Environment

Event	Event Type	Default Event Handler
15	creating parallel choice point	fail / 0
16	failing to parallel choice point	fail / 0
17	recomputation failed	error_handler / 2
20	arithmetic exception	error_handler / 2
21	undefined arithmetic expression	error_handler / 4
23	comparison trap	compare_handler / 4
24	number expected	error_handler / 2
25	integer overflow	integer_overflow_handler / 2
30	trying to write a read-only flag	error_handler / 2
31	arity limit exceeded	error_handler / 2
32	no handler for event	warning_handler / 2
33	event queue overflow	error_handler / 2

C.1.3 Data and Memory Areas, Predicates, Operators

Event	Event Type	Default Event Handler
40	stale object handle	error_handler / 2
41	array or global variable does not exist	undef_array_handler / 3
42	redefining an existing array	make_array_handler / 4
43	multiple definition postfix/infix	error_handler / 2
44	record already exists	error_handler / 2
45	record does not exist	undef_record_handler / 2
50	trying to modify a read-only ground term	error_handler / 2
60	referring to an undefined procedure	error_handler / 4
61	inconsistent tool redefinition	error_handler / 4
62	inconsistent procedure redefinition	error_handler / 4
63	procedure not dynamic	error_handler / 4
64	procedure already dynamic	dynamic_handler / 3
65	procedure already defined	error_handler / 4
66	trying to modify a system predicate	error_handler / 4
67	procedure is not yet loaded	error_handler / 4
68	calling an undefined procedure	call_handler / 4
69	autoload event	autoload_handler / 4
70	accessing an undefined dynamic procedure	undef_dynamic_handler / 3
71	procedure already parallel	error_handler / 2
72	accessing an undefined operator	error_handler / 2
73	redefining an existing operator	true / 0
74	hiding an existing global operator	true / 0
75	referring to a deprecated predicate	declaration_warning_handler / 3
76	predicate declared but not defined	declaration_warning_handler / 3
77	predicate used but not declared or defined	declaration_warning_handler / 3
78	calling a procedure with a reserved name	error_handler / 2

C.1.4 Modules, Visibility

Event	Event Type	Default Event Handler
80	not a module	error_handler / 2
81	module/1 can appear only as a directive	error_handler / 2
82	trying to access a locked module	locked_access_handler / 2
83	creating a new module	warning_handler / 2
84	referring to non-exported predicate	declaration_warning_handler / 3
85	referring to non-existing module	declaration_warning_handler / 3
86	lookup module does not exist	no_lookup_module_handler / 4
87	attempt to redefine an existing local item	warning_handler / 3
88	attempt to redefine an existing exported item	warning_handler / 3
89	attempt to redefine an already imported item	warning_handler / 3
90	procedure is already reexported	error_handler / 4
91	not a tool procedure	error_handler / 2
92	trying to redefine an existing local procedure	error_handler / 4
93	trying to redefine an existing exported procedure	error_handler / 4
94	trying to redefine an existing imported procedure	error_handler / 4
96	ambiguous import	ambiguous_import_resolve / 3
97	module already exists	error_handler / 2
98	key not correct	error_handler / 2
99	unresolved ambiguous import	ambiguous_import_warn / 3
100	accessing a procedure defined in another module	undef_dynamic_handler / 3
101	trying to erase a module from itself	error_handler / 2

C.1.5 Syntax Errors, Parsing

Event	Event Type	Default Event Handler
110	syntax error:	parser_error_handler / 2
111	syntax error: list tail ended improperly	parser_error_handler / 2
112	syntax error: illegal character in a quoted token	parser_error_handler / 2
113	syntax error: unexpected comma	parser_error_handler / 2
114	syntax error: unexpected token	parser_error_handler / 2
115	syntax error: unexpected end of file	parser_error_handler / 2
116	syntax error: numeric constant out of range	parser_error_handler / 2
117	syntax error: bracket necessary	parser_error_handler / 2
118	syntax error: unexpected fullstop	parser_error_handler / 2
119	syntax error: postfix/infix operator expected	parser_error_handler / 2
120	syntax error: wrong solo char	parser_error_handler / 2
121	syntax error: space between functor and open bracket	parser_error_handler / 2
122	syntax error: variable with multiple attributes	parser_error_handler / 2
123	illegal iteration specifier in do-loop	error_handler / 4
124	syntax error : prefix operator followed by infix operator	parser_error_handler / 2
125	syntax error : unexpected closing bracket	parser_error_handler / 2
126	syntax error : grammar rule head is not valid	parser_error_handler / 2
127	syntax error : grammar rule body is not valid	parser_error_handler / 2
128	syntax error : in source transformation	parser_error_handler / 2
129	syntax error: source transformation floundered	parser_error_handler / 2

C.1.6 Compilation, Run-Time System, Execution

Event	Event Type	Default Event Handler
130	syntax error: illegal head	compiler_error_handler / 2
131	syntax error: illegal goal	compiler_error_handler / 2
132	syntax error: term of an unknown type	compiler_error_handler / 2
133	loading the library	true / 0
134	procedure clauses are not consecutive	compiler_error_handler / 2
135	trying to redefine a protected procedure	compiler_error_handler / 2
136	trying to redefine a built-in predicate	compiler_error_handler / 2
137	trying to redefine a procedure with another type	compiler_error_handler / 2
138	singleton local variable in do-loop	singleton_in_loop / 2
139	compiled or dumped file message	compiled_file_handler / 3
140	undefined instruction	error_handler / 2
141	unimplemented functionality	error_handler / 2
142	built-in predicate not available on this system	error_handler / 2
143	compiled query failed	compiler_error_handler / 2
144	a cut is not allowed in a condition	compiler_error_handler / 2
145	procedure being redefined in another file	redef_other_file_handler / 2
146	start of compilation	true / 0
147	compilation aborted	compiler_abort_handler / 3
148	bad pragma	pragma_handler / 3
149	code unit loaded	unit_loaded_handler / 3

The handlers for these events receive the following arguments:

Event	Second Argument	Third Argument

130	Culprit clause	Module
131	Culprit clause	Module
132	Culprit clause	Module
133	Library name (string)	undefined
134	Procedure Name/Arity	Module
135	Procedure Name/Arity	Module
136	Procedure Name/Arity	Module
137	Procedure Name/Arity	Module
138	Variable name (atom)	undefined
139	(File, Size, Time), see below	Module
140	’Emulate’	undefined
141	Goal	Module
142	Goal	Module
143	Goal	Module
144	Goal (if an execution error) or Culprit clause (if compiler error)	Module
145	(Name/Arity, OldFile, NewFile)	Module
146	File	Module
147	File
148	Clause	Module

The second argument for the event 139 depends on the predicate where it was raised:

compile/1,2 - (file name, code size, compile time)
compile_stream/1 - (’string’, code size, compile time) with a string stream
compile_stream/1 - (file name, code size, compile time) with a stream associated to a file

C.1.7 Top-Level

Event	Event Type	Default Event Handler
150	start of eclipse execution	sepia_start / 0
151	eclipse restart	true / 0
152	end of eclipse execution	sepia_end / 0
153	toplevel: print prompt	toplevel_prompt / 2
154	toplevel: start of query execution	true / 0
155	toplevel: print values	print_values / 3
156	toplevel: print answer	tty_ask_more / 2
157	error exit	error_exit / 0
158	toplevel: entering break level	start_break / 3
159	toplevel: leaving break level	end_break / 3

These events are not errors but rather hooks to allow users to modify the behaviour of the ECLⁱPS^e toplevel. Therefore the arguments that are passed to the handler are not the erroneous goal and the context module but defined as follows:

Event	Second Argument	Third Argument

150	A free variable. If the handler binds the variable to an atom, this name is used as the toplevel module name	undefined
151	undefined	undefined
152	The argument is the number that ECLⁱPS^e will return to the operating system	undefined
153	current toplevel module	current toplevel module
154	a structure of the form goal(Goal, VarList, NewGoal, NewVarList), where Goal is the goal that is about to be executed and VarList is the list that associates the variables in Goal with their names (like in readvar/3 ). NewGoal and NewVarList are free variables. If the handler binds NewVarList then the toplevel will use NewGoal and NewVarList to replace Goal and VarList in the current query.	current toplevel module

Event	Second Argument	Third Argument

155	A list associating the variable names with their values after the query has been executed.	current toplevel module
156	An atom stating the answer to the query that was just executed. The possible values are: yes, last_yes or no if the query had no variables, more_answers, last_answer if the query contained variables and bindings were printed, no_answer if a query containing variables failed.	current toplevel module
157	undefined	undefined
158	break level	current toplevel module
159	break level	current toplevel module

When the handler for event 152 (“end of eclipse execution”) calls throw/1 , ECLⁱPS^e is not exited. This is a way to prevent accidental exits from the system. Failure of the handler is ignored.

C.1.8 Macro Transformation Errors, Lexical Analyser

Event	Event Type	Default Event Handler
160	global macro transformation already exists	error_handler / 4
161	macro transformation already defined in this module	macro_handler / 3
162	no macro transformation defined in this module	warning_handler / 2
163	illegal attempt to remove the last member of a character class	error_handler / 2
164	toplevel: print banner	tty_banner / 2
165	can’t compile an attributed variable (use add_attribute/2,3)	error_handler / 2
166	file successfully processed	record_compiled_file_handler / 3
167	initialization/finalization goal failed or aborted	warning_handler / 3

The event 164 is raised whenever the toplevel loop is restarted.

Event	Second Argument	Third Argument

164	the banner string

C.1.9 I/O, Operating System, External Interface

Event	Event Type	Default Event Handler
170	system interface error	system_error_handler / 4
171	File does not exist :	error_handler / 2
172	File is not open :	error_handler / 2
173	library not found	error_handler / 2
174	child process terminated due to signal	error_handler / 2
175	child process stopped	error_handler / 2
176	message passing error	error_handler / 2
177	shared library not found	error_handler / 2
190	end of file reached	eof_handler / 4
191	output error	output_error_handler / 4
192	illegal stream mode	error_handler / 2
193	illegal stream specification	error_handler / 2
194	too many symbolic names of a stream	error_handler / 2
195	yield on flush	io_yield_handler / 2
196	trying to modify a system stream	close_handler / 2
197	use ’input’ or ’output’ instead of ’user’	error_handler / 2
198	reading past the file end	past_eof_handler / 2
210	Remember() not inside a backtracking predicate	error_handler / 2
211	External function does not exist	error_handler / 2
212	External function returned invalid code	error_handler / 2
213	Error in external function	error_handler / 2
214	Licensing problem	error_handler / 2

C.1.10 Debugging, Object Files

Event	Event Type	Default Event Handler
230	uncaught exception	error_handler / 2
231	default help/0 message	fail / 0
249	debugger new suspensions event	bip_delay / 0
250	debugger init event	trace_start_handler_tty / 0
251	debugger builtin fail event	bip_port / 4
252	debugger port event	trace_line_handler_tty / 2
253	debugger call event	ncall / 2
254	debugger exit event	nexit / 1
255	debugger redo event	redo / 5
256	debugger delay event	ndelay / 2
257	debugger wake event	resume / 2
258	debugger builtin call event	bip_port / 4
259	debugger builtin exit event	bip_port / 4
260	unexpected end of file	error_handler / 2
261	invalid saved state	error_handler / 2
262	can not allocate required space	error_handler / 2
263	can not save or restore from another break level than level 0	error_handler / 2
264	not an eclipse object file	compiled_file_handler / 3
265	bad eclipse object file version	compiled_file_handler / 3
267	predicate not implemented in this version	error_handler / 2
268	predicate not supported in parallel session	error_handler / 2

These handlers receive special arguments:

Event	Second Argument	Third Argument

252	trace_line{port:Port,frame:Frame}	undefined
264	(File, [], [])	undefined
265	(File, [], [])	undefined

C.1.11 Extensions

Event	Event Type	Default Event Handler
270	undefined variable attribute	error_handler / 2
271	bad format of the variable attribute	error_handler / 2
272	delay clause may cause indefinite delay	warning_handler / 2
273	delayed goals left	delayed_goals_handler / 3
274	stack of woken lists empty	error_handler / 2
280	Found a solution with cost	cost_handler / 2

The handlers for these events receive the following arguments:

Event	Second Argument	Third Argument

272	Culprit clause	Module
273	list of sleeping suspensions	undefined
280	Cost, Goal	undefined