Class REXML::Source
In: lib/rexml/source.rb
Parent: Object

A Source can be searched for patterns, and wraps buffers and other objects and provides consumption of text

Methods

consume   current_line   empty?   encoding=   match   match_to   match_to_consume   new   position   read   scan  

Included Modules

Encoding

Attributes

buffer  [R]  The current buffer (what we‘re going to read next)
encoding  [R] 
line  [R]  The line number of the last consumed text

Public Class methods

new(arg, encoding=nil)

Constructor @param arg must be a String, and should be a valid XML document @param encoding if non-null, sets the encoding of the source to this value, overriding all encoding detection

[Source]

    # File lib/rexml/source.rb, line 40
40:     def initialize(arg, encoding=nil)
41:       @orig = @buffer = arg
42:       if encoding
43:         self.encoding = encoding
44:       else
45:         self.encoding = check_encoding( @buffer )
46:       end
47:       @line = 0
48:     end

Public Instance methods

consume( pattern )

[Source]

    # File lib/rexml/source.rb, line 90
90:     def consume( pattern )
91:       @buffer = $' if pattern.match( @buffer )
92:     end
current_line()

@return the current line in the source

[Source]

     # File lib/rexml/source.rb, line 120
120:     def current_line
121:       lines = @orig.split
122:       res = lines.grep @buffer[0..30]
123:       res = res[-1] if res.kind_of? Array
124:       lines.index( res ) if res
125:     end
empty?()

@return true if the Source is exhausted

[Source]

     # File lib/rexml/source.rb, line 111
111:     def empty?
112:       @buffer == ""
113:     end
encoding=(enc)

Inherited from Encoding Overridden to support optimized en/decoding

[Source]

    # File lib/rexml/source.rb, line 53
53:     def encoding=(enc)
54:       return unless super
55:       @line_break = encode( '>' )
56:       if enc != UTF_8
57:         @buffer = decode(@buffer)
58:         @to_utf = true
59:       else
60:         @to_utf = false
61:       end
62:     end
match(pattern, cons=false)

[Source]

     # File lib/rexml/source.rb, line 104
104:     def match(pattern, cons=false)
105:       md = pattern.match(@buffer)
106:       @buffer = $' if cons and md
107:       return md
108:     end
match_to( char, pattern )

[Source]

    # File lib/rexml/source.rb, line 94
94:     def match_to( char, pattern )
95:       return pattern.match(@buffer)
96:     end
match_to_consume( char, pattern )

[Source]

     # File lib/rexml/source.rb, line 98
 98:     def match_to_consume( char, pattern )
 99:       md = pattern.match(@buffer)
100:       @buffer = $'
101:       return md
102:     end
position()

[Source]

     # File lib/rexml/source.rb, line 115
115:     def position
116:       @orig.index( @buffer )
117:     end
read()

[Source]

    # File lib/rexml/source.rb, line 87
87:     def read
88:     end
scan(pattern, cons=false)

Scans the source for a given pattern. Note, that this is not your usual scan() method. For one thing, the pattern argument has some requirements; for another, the source can be consumed. You can easily confuse this method. Originally, the patterns were easier to construct and this method more robust, because this method generated search regexes on the fly; however, this was computationally expensive and slowed down the entire REXML package considerably, since this is by far the most commonly called method. @param pattern must be a Regexp, and must be in the form of /^\s*(#{your pattern, with no groups})(.*)/. The first group will be returned; the second group is used if the consume flag is set. @param consume if true, the pattern returned will be consumed, leaving everything after it in the Source. @return the pattern, if found, or nil if the Source is empty or the pattern is not found.

[Source]

    # File lib/rexml/source.rb, line 80
80:     def scan(pattern, cons=false)
81:       return nil if @buffer.nil?
82:       rv = @buffer.scan(pattern)
83:       @buffer = $' if cons and rv.size>0
84:       rv
85:     end

[Validate]