lib(iso_strict)


Overview
    This library provides an implementation of Standard Prolog as
    defined in ISO/IEC 13211-1 (Information Technology, Programming
    Languages, Prolog, Part 1, General Core, 1995) and the technical
    corrigenda ISO/IEC 13211-1 TC1 (2007) and TC2 (2012).
    The library is provided in source form.
    
    This library aims at providing a "strict mode" as required by ISO 13211-1,
    paragraph 5.1.e.  For non-strict versions, see library(iso) and
    library(iso_light).
    
Usage
    The effect of this compatibility library is (with minor exceptions)
    local to the module where it is loaded.  An ISO-program should always
    be contained in a separate module, starting with a directive like
    
    :- module(myisomodule, [], iso_strict).
    
    Here, the last argument of the module/3 directive indicates the language.
    It is not advisable to use ":-lib(iso_strict)" or
    ":-ensure_loaded(library(iso_strict))" within an eclipse_language module,
    because this would lead to import conflicts between the different
    versions of built-in predicates.
    
    Alternatively, in order to use ISO-Prolog without having different
    modules, one can invoke eclipse with a "-L iso_strict" command line option,
    or set the ECLIPSEDEFFAULTLANGUAGE environment variable to 'iso_strict'.
    This will launch eclipse with a default module accepting 'iso_strict'
    language instead of the usual 'eclipse_language'.
    
Specification of implementation defined features
    
    6.5 Processor characted set
	The PCS is the ISO 8859-1 character set.  Classification of
	extended characters: 7f-a0 layout; a1-bf, d7, f7 graphic;
	c0-d6, d8-f6, f8-ff alphanumeric.
    6.6 Collating sequence
	The collating sequence is that of the ISO 8859-1 character set
    7.1.2.2 Character codes
	Each character maps to a corresponding byte
    7.1.4.1 Characters
	As in the ISO 8859-1 character set
    7.2.1 Variable term order
	Older variables precede newer variables
    7.4.2.4,5 op/3 and char_conversion/2
	An operator or character-conversion defined in a directive is
	effective at runtime, and only in the module in which it occurs
    7.4.2.6 initialization/1
	Initialization goals are executed in the order in which they
	occur in the Prolog text
    7.4.2.7 include/1
	The argument is a file name atom according to ECLiPSe's canonical
	file name syntax, or a term of the form library(atom)
    7.4.2.8 ensure_loaded/1
	The argument is a file name atom according to ECLiPSe's canonical
	file name syntax, or a term of the form library(atom).  A file will
	be loaded on the first occurrence of ensure_loaded/1 in a prolog text,
	and if the file has been modified since the time it was first loaded.
	
    7.4.2.7 set_prolog_flag/2
	Flag setting are effective at runtime and globally (except for
	a few module-local flags in non-strict mode, see set_flag/2)
    7.5.1 Preparing for execution
	See the eclipse_language built-ins, menu items and command line
	options for compiling, loading and module handling, and also the
	instructions for using library(iso) or library(iso_strict)
    7.7.1,3 Execution and Initialization
	See the general ECLiPSe facilities, i.e. toplevel, graphical
	user interface and command line options
    7.10.1 Sources and sinks
	See open/3,4
    7.10.2.6 Text streams
	Text streams are very similar to binary streams, no characters
	are implicitly inserted or removed.  The nl/0,1 predicates emit
	an operating system and device dependent newline sequence.
    7.10.2.8,11 Stream positions
	File, string, and null streams can be (re)positioned
    7.10.2.9 End position of a stream
	The end position of a stream is the same as the position that
	a character appended to the stream would have
    7.10.2.11 Stream options
	The default eof_action is error
    7.10.2.13 Stream properties
	File names are atoms according to ECLiPSe's canonical file name
	syntax.
    7.11 Flags
	Fixed values: bounded=false, min_integer and max_integer fail,
	integer_rounding_function=toward_zero, max_arity=unbounded,
	char_conversion=off.
	Default values: double_quotes=chars, debug=off.
	If debug=on, the ECLiPSe tracer is active.  In non-strict mode,
	there is an additional flag max_predicate_arity, which indicates
	the limit on predicate arity (there is no limit on term arity).
	
    7.12.1 Effect of an error
	The implementation defined error term argument is normally the
	predicate indicator of the culprit goal.  For syntax errors, it is
	a term describing the error location.
    8.15.4 call/N
	The maximum N is given by the flag max_predicate_arity (255)
    8.17.1 set_prolog_flag/2
	The admissible flag values are the ones defined by ISO-Prolog (for
	iso_strict), plus those accepted by ECLiPSe's set_flag/2 (for iso)
    8.17.3,4 halt/0,1
	Exits the OS process with the given return code (or 0)
    9 Evaluable functors
        The 'exceptional values' are realized as follows: 'float_overflow'
	leads to a floating point infinity result; 'underflow' leads to
	a floating point denormalized value result; 'zero_divisor' leads
	to a floating point infinity result in the case of floats,
	or an evaluation_error(zero_divisor) in the case of integers;
	'int_overflow' does not occur and might lead to running out of
	memory instead.
    9.3 Other arithmetic operations
	When min/2 or max/2 are used with mixed integer and float
	arguments, the integer is coerced to float, and the result
	computed by comparing two floats
    9.4 Bitwise arithmetic operations
	The bitwise arithmetic operations behave as if operating on
	an unlimited length two's complement representation
    

Implementation specific features
    These are only available with library(iso), not with library(iso_strict)!
    
    7.10.2.11 Stream options
	For additional stream options, see open/4
    7.10.2.12 Options on stream closure
	None
    7.10.2.13 Stream properties
	For additional stream properties, see get_stream_info/3
    7.10.3 Read options
	For additional read options, see read_term/3
    7.10.4 Write options
	For additional stream options, see write_term/3
    7.11 Flags
	For additional Prolog flags, see get_flag/2
    

Remaining deviations from Standard
    
    The write predicates output extra spaces
    The char_conversion flag is always off, meaning that character
    conversion is not applied to prolog texts or on term input.  However,
    char_conversion/2 and current_char_conversion/2 predicates are operational.
    
    

