1	# src/codes: the stable id of every rule. A bolt.bend still names the slug
2	# (`wrap`); a diagnostic shows the code (`S003`) and, in an editor, the
3	# source `bolt(group:slug)`. Numbers are assigned once, in the group order
4	# of src/README.md: do not renumber a rule, and do not reuse a retired code
5	# (L004 was `quantify`, now `closed` itself; C001 was `shadow` and U005 was
6	# `nat`, whose failures bend 2.0.25 no longer has; U014 was `argv`, retired
7	# before its first release, since every reader already drops the program;
8	# U008 `table`, U009 `hoist`, U010 `ring`, U012 `unit` and U013 `scan` were
9	# retired for want of real hits, and L003 `unsafe` since bend 2.0.32 reports
10	# an unsafe def a proof reaches itself). A code names the rule, not its
11	# group: a rule that moves keeps its code (`strings` and `chars` are `perf`,
12	# `foreign` and the cost rules `fuel`, `index`, `strict` and `rewalk` are
13	# `pedantic`).
14	#
15	# No law can say this, since it is about versions: a released code is never
16	# renumbered or reused, which review of this table keeps.
17	import Base
18	import ./lazy/lazy.bend as Lazy
19	
20	# one rule: the slug bolt.bend names, its code, its group
21	type Entry is Data:
22	  Entry{slug: String, id: String, grp: String}
23	
24	# every rule, in group order
25	def table() -> List<&2, Entry>:
26	  [
27	    Entry{"hole", "C002", "correctness"},
28	    Entry{"pick", "C003", "correctness"},
29	    Entry{"put", "C004", "correctness"},
30	    Entry{"arms", "C005", "correctness"},
31	    Entry{"escape", "C006", "correctness"},
32	    Entry{"twice", "C007", "correctness"},
33	    Entry{"setting", "C011", "correctness"},
34	    Entry{"unused", "U001", "suspicious"},
35	    Entry{"eager", "U003", "suspicious"},
36	    Entry{"concat", "U004", "suspicious"},
37	    Entry{"thunk", "U015", "suspicious"},
38	    Entry{"fromrev", "U016", "suspicious"},
39	    Entry{"prefix", "U017", "suspicious"},
40	    Entry{"empty", "U018", "suspicious"},
41	    Entry{"strings", "C008", "perf"},
42	    Entry{"chars", "C009", "perf"},
43	    Entry{"doc", "S001", "style"},
44	    Entry{"space", "S002", "style"},
45	    Entry{"wrap", "S003", "style"},
46	    Entry{"param", "S004", "style"},
47	    Entry{"noqa", "S005", "style"},
48	    Entry{"transcong", "S006", "style"},
49	    Entry{"coverage", "L001", "laws"},
50	    Entry{"closed", "L002", "laws"},
51	    Entry{"foreign", "C010", "pedantic"},
52	    Entry{"strict", "U002", "pedantic"},
53	    Entry{"fuel", "U006", "pedantic"},
54	    Entry{"index", "U007", "pedantic"},
55	    Entry{"rewalk", "U011", "pedantic"},
56	    Entry{"tail", "P001", "pedantic"}]
57	
58	# this row is the slug
59	def find.same(+row: Entry, +slug: String) -> Bool:
60	  Entry{+s, _id, _grp} = row
61	  String.eq(s, slug)
62	
63	# the row for a slug
64	def find(rows: List<&2, Entry>, +slug: String) -> Maybe<&2, Entry>:
65	  match rows:
66	    case Nil{}:
67	      None{}
68	    case Con{+row, rest}:
69	      Lazy.stop(Maybe<&2, Entry>, find.same(row, slug), Some{row}, _u => find(rest, slug))
70	
71	# the stable code; the slug itself when it is not a rule
72	def code.at(mm: Maybe<&2, Entry>, +slug: String) -> String:
73	  match mm:
74	    case None{}:
75	      slug
76	    case Some{Entry{_s, +id, _grp}}:
77	      id
78	
79	# the stable code; the slug itself when it is not a rule
80	def code(+slug: String) -> String:
81	  code.at(find(table(), slug), slug)
82	
83	# the group; empty when the slug is not a rule
84	def group.at(mm: Maybe<&2, Entry>) -> String:
85	  match mm:
86	    case None{}:
87	      ""
88	    case Some{Entry{_s, _id, +grp}}:
89	      grp
90	
91	# the group; empty when the slug is not a rule
92	def group(+slug: String) -> String:
93	  group.at(find(table(), slug))
94	
95	# `bolt(group:slug)`; `bolt` when the slug is not a rule
96	def source.at(mm: Maybe<&2, Entry>) -> String:
97	  match mm:
98	    case None{}:
99	      "bolt"
100	    case Some{Entry{+s, _id, +grp}}:
101	      "bolt(" ++ grp ++ ":" ++ s ++ ")"
102	
103	# `bolt(group:slug)`; `bolt` when the slug is not a rule
104	def source(+slug: String) -> String:
105	  source.at(find(table(), slug))