Stdlib completion effort

Copied from https://github.com/tezena/PeTTa-and-MeTTa-comparisons/blob/main/README.md, thank you @tezena and @hal-29

There will be fast iteration in the coming days to complete and correct Stdlib.

MeTTa vs PeTTa interpreter comparison and observations

No	Test Case	H-E	PeTTa	Observations
1	!(bind! A B)	✅	⚠️	For space and states but not general atom binding
2	!(union-atom (1 2) (3 4))	✅	✅	Works on both
3	!(cons-atom 0 (1 2 3))	✅	✅	Works on both
4	!(intersection-atom (1 2) (3 4))	✅	✅	Works on both
5	!(car-atom (1 2 3))	✅	✅	Works on both
6	!(cdr-atom (1 2 3))	✅	✅	Works on both
7	!(superpose (1 2 3))	✅	✅	Works on both
8	!(collapse (superpose(1 2 3)))	✅	✅	Works on both
9	!(index-atom (1 2 3) 1)	✅	✅	Works on both
10	!(size-atom (1 2 3))	✅	✅	Works on both
11	!(sort-atom (3 1 4 2 3))	❌	✅	Works only on PeTTa

Extended built-ins coverage

Below are additional built-ins tested from the MeTTa stdlib pages. Each row shows whether it worked under MeTTa and PeTTa in this workspace, plus a brief note. Tests live alongside this document as .metta files named tests_*.metta.

Equality and Reduction

No	Test Case	H-E	PeTTa	Observations
10	(= (add 1 2) 3)	✅	✅	Works on both
11	!(id 5)	✅	✅	Works on both
12	!(=alpha (Father $X) (Father $Y))	✅	✅	Works on both
13	!(=alpha (Father $X) (Son $X))	✅	✅	Works on both
14	!(if-equal 1 1 "Equal" "Not Equal")	✅	✅	Works via !(import! &self lib_he)

Assertions

No	Test Case	H-E	PeTTa	Observations
15	!(assertEqual (+ 1 2) (- 6 3))	✅	✅	Works via !(import! &self lib_he)
16	!(assertAlphaEqual (h $x $y) (h $a $b))	✅	✅	Works via !(import! &self lib_he)
16	!(assertAlphaEqual (+ $x $y) (+ $a $b))	✅	⚠️	Needs !(import! &self lib_he) but with quote since + does not typecheck for performance reasons.
17	!(assertEqualToResult (+ 1 2) 3)	✅	❌	MeTTa implementation anyone?
18	!(assertAlphaEqualToResult (adder) ($y)) with (= (adder) $x)	✅	❌	MeTTa implementation anyone?

Error Handling

No	Test Case	H-E	PeTTa	Observations
19	!(Error (add "a" 2) BadType)	✅	✅	Works in both, but for an expression to return an error instead of returning (empty) it must use catch, e.g. (catch (+ a 2)).
20	!(if-error (Error 5 BadType) "Error!" "No error")	✅	✅	Works via !(import! &self lib_he)
21	!(return-on-error (Error 5 BadType) 6)	✅	✅	Works via !(import! &self lib_he)

Evaluation Control

No	Test Case	H-E	PeTTa	Observations
22	!(function (return 5))	✅	❌	Not planned.
23	!(eval (double 5)) with (= (double $x) (+ $x $x))	✅	✅	Works in both
24	!(evalc (+ 5 5) &self)	✅	✅	Works via !(import! &self lib_he)
25	!(chain (+ 2 3) $x (* $x 2))	✅	✅	Works in both
26	!(for-each-in-atom (1 3 5 62 2 5) println!)	✅	✅	Works via !(import! &self lib_he)

Mathematical Operations

No	Test Case	H-E	PeTTa	Observations
27	!(pow-math 2 3)	✅	✅	Works on both
28	!(sqrt-math 9)	✅	✅	Works on both
29	!(abs-math -5)	✅	✅	Works on both
30	!(log-math 10 100)	✅	✅	Works on both
31	!(trunc-math 5.6)	✅	✅	Works on both
32	!(ceil-math 5.2)	✅	✅	Works on both
33	!(floor-math 5.8)	✅	✅	Works on both
34	!(round-math 5.4)	✅	✅	Works on both
35	!(round-math 5.6)	✅	✅	Works on both
36	!(sin-math 0)	✅	✅	Works on both
37	!(asin-math 0)	✅	✅	Works on both
38	!(cos-math 0)	✅	✅	Works on both
39	!(acos-math 1)	✅	✅	Works on both
40	!(tan-math 0)	✅	✅	Works on both
41	!(atan-math 0)	✅	✅	Works on both
42	!(isnan-math 0.0)	✅	✅	Works on both
43	!(isinf-math 0.0)	✅	✅	Works on both
44	!(min-atom (2 6 7 4 9 3))	✅	✅	Works on both
45	!(max-atom (2 6 7 4 9 3))	✅	✅	Works on both

Non-deterministic Computation

No	Test Case	MeTTa	PeTTa	Observations
46	!(superpose (A B C))	✅	✅	Works on both
47	!(collapse (superpose (A B C)))	✅	✅	Works on both

Type System

No	Test Case	H-E	PeTTa	Observations
48	!(is-function (-> Atom Atom))	✅	✅	Works via !(import! &self lib_he)
49	!(is-function Atom)	✅	✅	Works via !(import! &self lib_he)
50	!(type-cast A type1 &self) with (: type1 Type)	✅	❌	Not planned.
51	!(type-cast 1 type1 &self)	✅	❌	Not planned.
52	!(match-types Atom Atom "Matched!" "Didn't match")	✅	✅	Works via !(import! &self lib_he)
53	!(match-types Atom Number "Matched!" "Didn't match")	✅	✅	Works via !(import! &self lib_he)
54	!(first-from-pair (A B))	✅	✅	Works on both
55	!(second-from-pair (A B))	❌	✅	Works only in PeTTa
55	!(match-type-or True Number Bool)	✅	✅	Works via !(import! &self lib_he)

List Manipulation

No	Test Case	H-E	PeTTa	Observations
56	!(foldl-atom (1 2 3 4) 0 $acc $x (+ $acc $x))	✅	✅	Works on both
57	!(map-atom (1 2 3) $x (+ $x 1))	✅	✅	Works on both
58	!(filter-atom (1 2 3 4 5) $x (> $x 3))	✅	✅	Works on both
59	!(foldl-atom (1 2 3 4) 0 foldfunc)	❌	✅	Works only on PeTTa
60	!(map-atom (1 2 3) mapfunc)	❌	✅	Works only on PeTTa
61	!(filter-atom (1 2 3 4 5) filterfunc)	❌	✅	Works only on PeTTa

Atomspace Interaction

No	Test Case	H-E	PeTTa	Observations
59	!(add-reduct &self (= (add) (+ 1 3)))	✅	✅	Works via !(import! &self lib_he)
60	!(add-atom &self (= (add) (+ 1 3)))	✅	✅	Works on both
61	!(get-type 1)	✅	✅	Works in both
62	(: a A) then !(get-type-space &self a)	✅	✅	Works via !(import! &self lib_he)
63	!(get-metatype True)	✅	✅	Works on both
64	!(get-metatype (a b))	✅	✅	Works on both
65	!(new-space)	✅	✅	Returns new space ref in MeTTa; PeTTa unevaluated yet new spaces can be manipulated nevertheless.
66	!(bind! state (new-state rest))	✅	✅	Works on both
67	!(change-state! state active) then !(get-state state)	✅	✅	Works on both
68	!(get-atoms &self)	✅	✅	Works on both
69	!(match &self (= (add) (+ $x $y)) $x)	✅	✅	Works on both

Quoting

No	Test Case	H-E	PeTTa	Observations
70	!(quote (+ 1 2))	✅	✅	MeTTa returns (quote (+ 1 2)), PeTTa returns (+ 1 2) unreduced.
71	!(unquote (quote (+ 1 2)))	✅	✅	Works via !(import! &self lib_he)
73	!(noreduce-eq (+ 1 2) (+ 1 2))	✅	✅	Works via !(import! &self lib_he)
74	!(noreduce-eq (+ 1 2) 3)	✅	✅	Works via !(import! &self lib_he)

Set Operations

No	Test Case	H-E	PeTTa	Observations
75	!(unique (superpose (a b c d d)))	✅	✅	Works on both
76	!(union (superpose (a b b c)) (superpose (b c c d)))	✅	✅	Works on both
77	!(intersection (superpose (a b c c)) (superpose (b c c c d)))	✅	✅	Works on both
78	!(subtraction (superpose (a b b c)) (superpose (b c c d)))	✅	✅	Works on both
79	!(unique-atom (a b c d d))	✅	✅	Works on both
80	!(union-atom (a b b c) (b c c d))	✅	✅	Works on both
81	!(intersection-atom (a b c c) (b c c c d))	✅	✅	Works on both
82	!(subtraction-atom (a b b c) (b c c d))	✅	✅	Works on both