Class Citrus::Input

  1. lib/citrus.rb
Parent: StringScanner

An Input is a scanner that is responsible for executing rules at different positions in the input string and persisting event streams.

Methods

public class

  1. new

public instance

  1. exec
  2. line
  3. line_index
  4. line_number
  5. line_offset
  6. lineno
  7. lines
  8. memoized?
  9. test

External Aliases

string -> to_str
  Returns the scanned string.

Attributes

max_offset [R] The maximum offset in the input that was successfully parsed.
source [R] The initial source passed at construction. Typically a String or a Pathname.

Public class methods

new (source)
[show source] 
     # File lib/citrus.rb, line 173
173:     def initialize(source)
174:       super(source_text(source))
175:       @source = source
176:       @max_offset = 0
177:     end

Public instance methods

exec (rule, events=[])

Returns an array of events for the given rule at the current pointer position. Objects in this array may be one of three types: a Rule, Citrus::CLOSE, or a length (integer).

[show source] 
     # File lib/citrus.rb, line 246
246:     def exec(rule, events=[])
247:       position = pos
248:       index = events.size
249: 
250:       if apply_rule(rule, position, events).size > index
251:         @max_offset = pos if pos > @max_offset
252:       else
253:         self.pos = position
254:       end
255: 
256:       events
257:     end
line (pos=pos)

Returns the text of the line that contains the character at the given pos. pos defaults to the current pointer position.

[show source] 
     # File lib/citrus.rb, line 234
234:     def line(pos=pos)
235:       lines[line_index(pos)]
236:     end
line_index (pos=pos)

Returns the 0-based number of the line that contains the character at the given pos. pos defaults to the current pointer position.

[show source] 
     # File lib/citrus.rb, line 214
214:     def line_index(pos=pos)
215:       p = n = 0
216:       string.each_line do |line|
217:         p += line.length
218:         return n if p >= pos
219:         n += 1
220:       end
221:       0
222:     end
line_number (pos=pos)

Returns the 1-based number of the line that contains the character at the given pos. pos defaults to the current pointer position.

[show source] 
     # File lib/citrus.rb, line 226
226:     def line_number(pos=pos)
227:       line_index(pos) + 1
228:     end
line_offset (pos=pos)

Returns the 0-based offset of the given pos in the input on the line on which it is found. pos defaults to the current pointer position.

[show source] 
     # File lib/citrus.rb, line 202
202:     def line_offset(pos=pos)
203:       p = 0
204:       string.each_line do |line|
205:         len = line.length
206:         return (pos - p) if p + len >= pos
207:         p += len
208:       end
209:       0
210:     end
lineno (pos=pos)

Alias for line_number

lines ()

Returns an array containing the lines of text in the input.

[show source] 
     # File lib/citrus.rb, line 192
192:     def lines
193:       if string.respond_to?(:lines)
194:         string.lines.to_a
195:       else
196:         string.to_a
197:       end
198:     end
memoized? ()

Returns true when using memoization to cache match results.

[show source] 
     # File lib/citrus.rb, line 239
239:     def memoized?
240:       false
241:     end
test (rule)

Returns the length of a match for the given rule at the current pointer position, nil if none can be made.

[show source] 
     # File lib/citrus.rb, line 261
261:     def test(rule)
262:       position = pos
263:       events = apply_rule(rule, position, [])
264:       self.pos = position
265:       events[-1]
266:     end