1		:- multifile generate/2.
2		:- multifile shrink/3.
3
4		:- use_module(library(random),[random_member/2]).
5
6		generate(prob_ast_seq_expr,Value) :-
7		generate(prob_ast_seq_expr([]),Value).
8
9		% Options:
10		% id to enable random generation of identifier
11		% not-well-defined
12
13		% Expr :: seq(_)
14		generate(prob_ast_seq_expr(Options),Value) :-
15		random_member(Expr,[empty_sequence,front,tail,rev,concat,insert_front,insert_tail,
16		restrict_front,restrict_tail,general_concat]) ,
17		generate(prob_ast_seq_expr(Expr,Options),Value).
18
19		generate(prob_ast_seq_expr(empty_sequence,_),b(sequence_extension([]),seq(empty),[])).
20
21		generate(prob_ast_seq_expr(general_concat,Options),b(general_concat(SeqOfSeq),SeqType,[])) :-
22		generate(ground_type,Ground) ,
23		generate(prob_ast_seq(seq(Ground),Options),SeqOfSeq) ,
24		SeqOfSeq = b(_,seq(SeqType),_).
25
26		generate(prob_ast_seq_expr(Type,Options),b(NewExpr,SeqType,[])) :-
27		member(Type,[front,tail,rev]) ,
28		generate(ground_type,InnerType) ,
29		(member(id,Options)
30		-> generate(id_or_ast(seq(InnerType)),Seq)
31		; generate(prob_ast_seq(InnerType,Options),Seq)) ,
32		Seq = b(_,SeqType,_) ,
33		NewExpr =.. [Type,Seq].
34
35		% not well defined when trying to restrict front by
36		% more values than the sequence contains
37		generate(prob_ast_seq_expr(Type,Options),b(NewExpr,SeqType,[])) :-
38		member(not-well-defined,Options) ,
39		member(Type,[restrict_front,restrict_tail]) ,
40		generate(prob_ast_seq_expr(Options),Seq) ,
41		Seq = b(_,SeqType,_) ,
42		generate(prob_ast_integer([small,positive]),Value) ,
43		NewExpr =.. [Type,Seq,Value].
44		% generate integer in the range of the sequence size
45		generate(prob_ast_seq_expr(Type,Options),b(NewExpr,SeqType,[])) :-
46		member(Type,[restrict_front,restrict_tail]) ,
47		generate(ground_type,Ground) ,
48		generate(prob_ast_seq(Ground,[extension|Options]),Seq) ,
49		Seq = b(sequence_extension(Set),SeqType,_) ,
50		length(Set,Length) ,
51		generate(prob_ast_integer([small,between(0,Length)]),Value) ,
52		NewExpr =.. [Type,Seq,Value].
53
54		generate(prob_ast_seq_expr(concat,Options),b(concat(Seq1,Seq2),seq(Type),[])) :-
55		generate(prob_ast_seq_expr(Options),Seq1) ,
56		Seq1 = b(_,seq(Type),_) ,
57		(Type = empty
58		-> Seq2 = b(sequence_extension([]),seq(empty),[])
59		; inner_type(Type,Inner,Outter) ,
60		NewInner =.. [Inner,[]] , % no options
61		surround_type(NewInner,Outter,NType) ,
62		(member(id,Options) , Type \= empty
63		-> generate(id_or_ast(seq(NType)),Seq2)
64		; generate(prob_ast_seq(NType,Options),Seq2))).
65
66		generate(prob_ast_seq_expr(insert_front,Options),b(insert_front(Value,ValueSeq),seq(SeqType),[])) :-
67		generate(prob_ast_seq_expr(Options),ValueSeq) ,
68		ValueSeq = b(_,seq(Type),_) ,
69		(Type = empty
70		-> generate(ground_type,NType) ,
71		NType =.. [SeqType,_]
72		; inner_type(Type,Inner,Outter) ,
73		NewInner =.. [Inner,[]] ,
74		surround_type(NewInner,Outter,NType) ,
75		Type = SeqType) ,
76		(member(id,Options)
77		-> generate(id_or_ast(seq(NType)),Value)
78		; gen_type(NType,ast,GenType) ,
79		generate(GenType,Value)).
80
81		generate(prob_ast_seq_expr(insert_tail,Options),b(insert_tail(ValueSeq,Value),seq(SeqType),[])) :-
82		generate(prob_ast_seq_expr(Options),ValueSeq) ,
83		ValueSeq = b(_,seq(Type),_) ,
84		(Type = empty
85		-> generate(ground_type,NType) ,
86		NType =.. [SeqType,_]
87		; inner_type(Type,Inner,Outter) ,
88		NewInner =.. [Inner,[]] ,
89		surround_type(NewInner,Outter,NType) ,
90		Type = SeqType) ,
91		(member(id,Options)
92		-> generate(id_or_ast(seq(NType)),Value)
93		; gen_type(NType,ast,GenType) ,
94		generate(GenType,Value)).
95
96		shrink(Type,Value,Shrunken) :-
97		Type =.. [prob_ast_seq_expr|_] ,
98		minimize_seq_expr(Value,Shrunken).
99
100		shrink(Type,Value,Shrunken) :-
101		Type =.. [prob_ast_seq_expr|_] ,
102		% defined in prob_ast_minimize_int_expr.pl
103		get_inner_expr(Value,Shrunken).