1	# src/paths: what a path names, read by its segments, never by a suffix or a
2	# substring. A law file is one whose last segment is exactly LAWS.bend or
3	# PROOF.bend, so OUTLAWS.bend is not one; a test is one with a directory
4	# segment exactly `tests`, so contests/ is not one. Pure.
5	import Base
6	import ./lazy/lazy.bend as Lazy
7	
8	# the last of the segments, or the one before when there are none
9	def base.go(segs: List<&2, String>, last: String) -> String:
10	  match segs:
11	    case Nil{}:
12	      last
13	    case Con{s, rest}:
14	      base.go(rest, s)
15	
16	# a path's last segment
17	def base(path: String) -> String:
18	  base.go(String.split(path, '/'), "")
19	
20	# is some segment but the last exactly `tests`?
21	def tested(segs: List<&2, String>) -> Bool:
22	  match segs:
23	    case Nil{}:
24	      False{}
25	    case Con{+s, +rest}:
26	      Lazy.or_else(Bool.and(String.eq(s, "tests"), Bool.not(List.is_empty(&2, String, rest))), _u => tested(rest))
27	
28	# is the file under a `tests` directory?
29	def is_test(path: String) -> Bool:
30	  tested(String.split(path, '/'))
31	
32	# is it a LAWS.bend?
33	def is_laws(path: String) -> Bool:
34	  String.eq(base(path), "LAWS.bend")
35	
36	# is it a PROOF.bend?
37	def is_proof(path: String) -> Bool:
38	  String.eq(base(path), "PROOF.bend")
39	
40	# is it a LAWS.bend or a PROOF.bend?
41	def is_law_file(+path: String) -> Bool:
42	  Bool.or(is_laws(path), is_proof(path))