Module: RIEL::StringExt

Defined in:
lib/riel/string.rb

Constant Summary collapse

Infinity =

Represents infinity, for the to_ranges function.

(1.0 / 0)
RANGE_REGEXP =

:stopdoc:

from  (maybe   to           this)

%r{^ \s* (\d*) (?: \s* (\-|\.\.) \s* (\d*) )? \s* $ }x

Instance Method Summary collapse

Instance Method Details

#-(other) ⇒ Object

Returns a string based on this instance, with the first occurrance of other removed. other may be a string or regular expression.



37
38
39
 
# File 'lib/riel/string.rb', line 37

def - other
  sub other, ''
end

#_has_matchdata?(md, idx) ⇒ Boolean

:stopdoc:

Returns:

  • (Boolean) 


93
94
95
 
# File 'lib/riel/string.rb', line 93

def _has_matchdata? md, idx
  md && md[idx] && !md[idx].empty?
end

#_matchdata_to_number(md, idx, default) ⇒ Object 



97
98
99
 
# File 'lib/riel/string.rb', line 97

def _matchdata_to_number md, idx, default
  _has_matchdata?(md, idx) ? md[idx].to_i : default
end

#ends_with(substr) ⇒ Object

Returns whether the string ends with the given substring.



18
19
20
 
# File 'lib/riel/string.rb', line 18

def ends_with substr
  return rindex(substr) == length - substr.length
end

#num ⇒ Object

Returns the string, as a number if it is one, and nil otherwise,



25
26
27
28
29
30
31
 
# File 'lib/riel/string.rb', line 25

def num
  begin
    Integer self
  rescue ArgumentError
    nil
  end
end

#to_ranges(args = Hash.new) ⇒ Object

Splits num into array of ranges, limiting itself to args[:min] and args[:max], if specified. The args[:collapse], if true, results in sequential values put into the same range.

Examples:

"1,2".to_ranges                                   # [ 1 .. 1, 2 .. 2 ]
"1,2".to_ranges :collapse => true                 # [ 1 .. 2 ]
"1-4".to_ranges                                   # [ 1 .. 4 ]
"1-3,5-6,10,11,12,".to_ranges :collapse => true   # [ 1 .. 3, 5 .. 6, 10 .. 12 ]
"1-3,5-6,10,11,12,".to_ranges                     # [ 1 .. 3, 5 .. 6, 10 .. 10, 11 .. 11, 12 .. 12 ]
"-4".to_ranges                                    # [ -String::Infinity ..  4 ]
"4-".to_ranges                                    # [ 4 .. String::Infinity ]
"1-".to_ranges :min => 0, :max => 8               # [ 1 .. 8 ]



67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
 
# File 'lib/riel/string.rb', line 67

def to_ranges args = Hash.new
  min = args[:min] || -Infinity
  max = args[:max] || Infinity
  collapse = args[:collapse]
  
  ranges = Array.new
  self.split(%r{\s*,\s*}).each do |section|
    md = section.match(RANGE_REGEXP)
    next unless md
    
    from = _matchdata_to_number md, 1, min
    to = _has_matchdata?(md, 2) ? _matchdata_to_number(md, 3, max) : from

    prevrange = ranges[-1]

    if collapse && prevrange && prevrange.include?(from - 1) && prevrange.include?(to - 1)
      ranges[-1] = (prevrange.first .. to)
    else
      ranges << (from .. to)
    end
  end

  ranges
end