blob: 9fb1d79bba91f75f8d9fecf7897a87ea9c80c8c7 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
|
## Helper Methods
These helper methods display values returned by scanner's methods.
### `put_situation(scanner)`
Display scanner's situation:
- Byte position (`#pos`).
- Character position (`#charpos`)
- Target string (`#rest`) and size (`#rest_size`).
```rb
scanner = StringScanner.new('foobarbaz')
scanner.scan(/foo/)
put_situation(scanner)
# Situation:
# pos: 3
# charpos: 3
# rest: "barbaz"
# rest_size: 6
```
### `put_match_values(scanner)`
Display the scanner's match values:
```rb
scanner = StringScanner.new('Fri Dec 12 1975 14:39')
pattern = /(?<wday>\w+) (?<month>\w+) (?<day>\d+) /
scanner.match?(pattern)
put_match_values(scanner)
# Basic match values:
# matched?: true
# matched_size: 11
# pre_match: ""
# matched : "Fri Dec 12 "
# post_match: "1975 14:39"
# Captured match values:
# size: 4
# captures: ["Fri", "Dec", "12"]
# named_captures: {"wday"=>"Fri", "month"=>"Dec", "day"=>"12"}
# values_at: ["Fri Dec 12 ", "Fri", "Dec", "12", nil]
# []:
# [0]: "Fri Dec 12 "
# [1]: "Fri"
# [2]: "Dec"
# [3]: "12"
# [4]: nil
```
### `match_values_cleared?(scanner)`
Returns whether the scanner's match values are all properly cleared:
```rb
scanner = StringScanner.new('foobarbaz')
match_values_cleared?(scanner) # => true
put_match_values(scanner)
# Basic match values:
# matched?: false
# matched_size: nil
# pre_match: nil
# matched : nil
# post_match: nil
# Captured match values:
# size: nil
# captures: nil
# named_captures: {}
# values_at: nil
# [0]: nil
scanner.scan(/foo/)
match_values_cleared?(scanner) # => false
```
## The Code
```rb
def put_situation(scanner)
puts '# Situation:'
puts "# pos: #{scanner.pos}"
puts "# charpos: #{scanner.charpos}"
puts "# rest: #{scanner.rest.inspect}"
puts "# rest_size: #{scanner.rest_size}"
end
def put_match_values(scanner)
puts '# Basic match values:'
puts "# matched?: #{scanner.matched?}"
value = scanner.matched_size || 'nil'
puts "# matched_size: #{value}"
puts "# pre_match: #{scanner.pre_match.inspect}"
puts "# matched : #{scanner.matched.inspect}"
puts "# post_match: #{scanner.post_match.inspect}"
puts '# Captured match values:'
puts "# size: #{scanner.size}"
puts "# captures: #{scanner.captures}"
puts "# named_captures: #{scanner.named_captures}"
if scanner.size.nil?
puts "# values_at: #{scanner.values_at(0)}"
puts "# [0]: #{scanner[0]}"
else
puts "# values_at: #{scanner.values_at(*(0..scanner.size))}"
puts "# []:"
scanner.size.times do |i|
puts "# [#{i}]: #{scanner[i].inspect}"
end
end
end
def match_values_cleared?(scanner)
scanner.matched? == false &&
scanner.matched_size.nil? &&
scanner.matched.nil? &&
scanner.pre_match.nil? &&
scanner.post_match.nil? &&
scanner.size.nil? &&
scanner[0].nil? &&
scanner.captures.nil? &&
scanner.values_at(0..1).nil? &&
scanner.named_captures == {}
end
```
|
