quintus.pl -- Quintus compatibility
This module defines several predicates from the Quintus Prolog libraries. Note that our library structure is totally different. If this library were complete, Prolog code could be ported by removing the use_module/1 declarations, relying on the SWI-Prolog autoloader.
Bluffers guide to porting:
- Remove
use_module(library(...)) - Run
?- list_undefined. - Fix problems
Of course, this library is incomplete ...
- unix(+Action)
- This predicate provides a partial emulation of the corresponding
Quintus predicate. It provides access to some operating system
features and unlike the name suggests, is not operating system
specific. Defined actions are below.
- system(+Command)
- Equivalent to
shell(Command) - shell(+Command)
- Equivalent to
shell(Command) - access(File, 0)
- Equivalent to
access_file(File, read) - cd(Dir)
- Equivalent to
working_directory(_, Dir) - args(List)
- Equivalent to
current_prolog_flag(os_argv, List). - argv(List)
- Equivalent to
args(List), but arguments that are syntactically valid numbers are passed as a number.
- otherwise
- For (A -> B ; otherwise -> C)
- abs(+Number, -Absolute)
- Unify `Absolute' with the absolute value of `Number'.
- sin(+Angle, -Sine) is det
- cos(+Angle, -Cosine) is det
- tan(+Angle, -Tangent) is det
- log(+X, -NatLog) is det
- log10(+X, -Log) is det
- pow(+X, +Y, -Pow) is det
- ceiling(+X, -Value) is det
- floor(+X, -Value) is det
- round(+X, -Value) is det
- sqrt(+X, -Value) is det
- acos(+X, -Value) is det
- asin(+X, -Value) is det
- atan(+X, -Value) is det
- atan2(+Y, +X, -Value) is det
- sign(+X, -Value) is det
- Math library predicates. SWI-Prolog (and ISO) support these as functions under is/2, etc.
- genarg(?Index, +Term, ?Arg) is nondet
- Generalised version of ISO arg/3. SWI-Prolog's arg/3 is already genarg/3.
- prolog_flag(?Flag, ?Value) is nondet
- Same as ISO current_prolog_flag/2. Maps
version. - date(-Date) is det
- Get current date as
date(Y,M,D) - no_style_check(Style) is det
- Same as SWI-Prolog
style_check(-Style). The Quintus optionsingle_varis mapped tosingleton. - mode(+ModeDecl) is det
- Ignore a DEC10/Quintus
:- mode(Head)declaration. Typically these declarations are written in operator form. The operator declaration is not part of the Quintus emulation library. The following declaration is compatible with Quintus::- op(1150, fx, [(mode)]).
- simple(@Term) is semidet
- Term is atomic or a variable.
- current_stream(?Object, ?Mode, ?Stream)
- SICStus/Quintus and backward compatible predicate. New code should be using the ISO compatible stream_property/2.
- stream_position(+Stream, -Old, +New)
- True when Old is the current position in Stream and the stream has been repositioned to New.
- skip_line is det
- skip_line(Stream) is det
- Skip the rest of the current line (on Stream). Same as
skip(0'\n). - compile(+Files) is det
- Compile files. SWI-Prolog doesn't distinguish between compilation and consult.
- atom_char(+Char, -Code) is det
- atom_char(-Char, +Code) is det
- Same as ISO char_code/2.
- midstring(?ABC, ?B, ?AC) is nondet
- midstring(?ABC, ?B, ?AC, LenA) is nondet
- midstring(?ABC, ?B, ?AC, LenA, LenB) is nondet
- midstring(?ABC, ?B, ?AC, LenA, LenB, LenC) is nondet
- Too difficult to explain. See the Quintus docs. As far as I understand them the code below emulates this function just fine.
- raise_exception(+Term)
- Quintus compatible exception handling
- on_exception(+Template, :Goal, :Recover)
Undocumented predicates
The following predicates are exported, but not or incorrectly documented.
- sqrt(Arg1, Arg2)
- acos(Arg1, Arg2)
- pow(Arg1, Arg2, Arg3)
- cos(Arg1, Arg2)
- midstring(Arg1, Arg2, Arg3, Arg4)
- skip_line(Arg1)
- asin(Arg1, Arg2)
- ceiling(Arg1, Arg2)
- tan(Arg1, Arg2)
- midstring(Arg1, Arg2, Arg3, Arg4, Arg5)
- atan(Arg1, Arg2)
- atan2(Arg1, Arg2, Arg3)
- floor(Arg1, Arg2)
- log(Arg1, Arg2)
- midstring(Arg1, Arg2, Arg3, Arg4, Arg5, Arg6)
- sign(Arg1, Arg2)
- round(Arg1, Arg2)
- log10(Arg1, Arg2)