REXML::Source (Class)

In: 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   read   scan  

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

Included Modules

Encoding

Public Class methods

new(arg)

Constructor @param arg must be a String, and should be a valid XML document

[Source]

# File rexml/source.rb, line 31
                def initialize(arg)
                        @orig = @buffer = arg
                        self.encoding = check_encoding( @buffer )
                        @line = 0
                end

Public Instance methods

consume( pattern )

[Source]

# File rexml/source.rb, line 76
                def consume( pattern )
                        @buffer = $' if pattern.match( @buffer )
                end
current_line()

@return the current line in the source

[Source]

# File rexml/source.rb, line 102
                def current_line
                        lines = @orig.split
                        res = lines.grep @buffer[0..30]
                        res = res[-1] if res.kind_of? Array
                        lines.index( res ) if res
                end
empty?()

@return true if the Source is exhausted

[Source]

# File rexml/source.rb, line 97
                def empty?
                        @buffer == ""
                end
encoding=(enc)

Inherited from Encoding Overridden to support optimized en/decoding

[Source]

# File rexml/source.rb, line 39
                def encoding=(enc)
                        super
                        @line_break = encode( '>' )
                        if enc != UTF_8
                                @buffer = decode(@buffer)
                                @to_utf = true
                        else
                                @to_utf = false
                        end
                end
match(pattern, cons=false)

[Source]

# File rexml/source.rb, line 90
                def match(pattern, cons=false)
                        md = pattern.match(@buffer)
                        @buffer = $' if cons and md
                        return md
                end
match_to( char, pattern )

[Source]

# File rexml/source.rb, line 80
                def match_to( char, pattern )
                        return pattern.match(@buffer)
                end
match_to_consume( char, pattern )

[Source]

# File rexml/source.rb, line 84
                def match_to_consume( char, pattern )
                        md = pattern.match(@buffer)
                        @buffer = $'
                        return md
                end
read()

[Source]

# File rexml/source.rb, line 73
                def read
                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 rexml/source.rb, line 66
                def scan(pattern, cons=false)
                        return nil if @buffer.nil?
                        rv = @buffer.scan(pattern)
                        @buffer = $' if cons and rv.size>0
                        rv
                end

[Validate]