Class: PatternParser

Inherits:
Object
  • Object
show all
Defined in:
lib/pattern_expander/pattern_parser.rb

Constant Summary collapse

DEFAULT_SUBSTITUTES = 
{
  "+w" => ('a'..'z').to_a + ('0'..'9').to_a,
  "+d" => ('0'..'9').to_a,
}

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(substitutes: DEFAULT_SUBSTITUTES) ⇒ PatternParser

Returns a new instance of PatternParser.



9
10
11
12
 
# File 'lib/pattern_expander/pattern_parser.rb', line 9

def initialize(substitutes: DEFAULT_SUBSTITUTES)
  @substitutes = substitutes
  @delimiter = '|'
end

Instance Attribute Details

#delimiter ⇒ Object (readonly)

Returns the value of attribute delimiter.



2
3
4
 
# File 'lib/pattern_expander/pattern_parser.rb', line 2

def delimiter
  @delimiter
end

#substitutes ⇒ Object (readonly)

Returns the value of attribute substitutes.



2
3
4
 
# File 'lib/pattern_expander/pattern_parser.rb', line 2

def substitutes
  @substitutes
end

Instance Method Details

#_parse_groups(string) ⇒ Object 



21
22
23
24
25
 
# File 'lib/pattern_expander/pattern_parser.rb', line 21

def _parse_groups(string)
  string.scan(
    /([^\[\]]+|[\#{delimiter}]+)/
  ).flatten
end

#_substitute(groups) ⇒ Object 



27
28
29
30
31
32
33
 
# File 'lib/pattern_expander/pattern_parser.rb', line 27

def _substitute(groups)
  groups.map do |group|
    group.inject([]) do |memo, item|
      memo += substitutes[item] || [item]
    end
  end
end

#parse(string) ⇒ Object 



14
15
16
17
18
19
 
# File 'lib/pattern_expander/pattern_parser.rb', line 14

def parse(string)
  parsed_groups = _parse_groups(string).map do |group|
    group.split(delimiter)
  end
  _substitute(parsed_groups)
end