Sets the previous sibling of this child. This can be used to insert a child before some other child.
a = Element.new("a") b = a.add_element("b") c = Element.new("c") b.previous_sibling = c # => <a><b/><c/></a>
Evaluates to the root node of the document that this element belongs to. If this element doesn’t belong to a document, but does belong to another Element, the parent’s root will be returned, until the earliest ancestor is found.
Note that this is not the same as the document element. In the following example, <a> is the document element, and the root node is the parent node of the document element. You may ask yourself why the root node is useful: consider the doctype and XML declaration, and any processing instructions before the document element… they are children of the root node, or siblings of the document element. The only time this isn’t true is when an Element is created that is not part of any Document. In this case, the ancestor that has no parent acts as the root node.
d = Document.new '<a><b><c/></b></a>' a = d[1] ; c = a[1][1] d.root_node == d # TRUE a.root_node # namely, d c.root_node # again, d
Returns the previous sibling that is an element, or nil if there is no Element sibling prior to this one
doc = Document.new '<a><b/>text<c/></a>' doc.root.elements['c'].previous_element #-> <b/> doc.root.elements['b'].previous_element #-> nil
Generates a Source object @param arg Either a String, or an IO @return a Source, or nil if a bad argument was given
Creates a socket at address
If address is multicast address then interface_address and multicast_interface can be set as optional.
A created socket is bound to interface_address. If you use IPv4 multicast then the interface of interface_address is used as the inbound interface. If interface_address is omitted or nil then ‘0.0.0.0’ or ‘::1’ is used.
If you use IPv6 multicast then multicast_interface is used as the inbound interface. multicast_interface is a network interface index. If multicast_interface is omitted then 0 (default interface) is used.
Indicated, based on the requested domain, if local gems should be considered.
Creates a DependencyList from the current specs.
Return a hash of predecessors. result[spec] is an Array of gemspecs that have a dependency satisfied by the named gemspec.
Compresses indices on disk
Turn an array of [name, version, platform] into an array of NameTuple objects.
Display an error message in a location expected to get error messages. Will ask question if it is not nil.
Creates an error page for exception ex with an optional backtrace
Returns the one-character string which cause Encoding::UndefinedConversionError.
ec = Encoding::Converter.new("ISO-8859-1", "EUC-JP") begin ec.convert("\xa0") rescue Encoding::UndefinedConversionError puts $!.error_char.dump #=> "\xC2\xA0" p $!.error_char.encoding #=> #<Encoding:UTF-8> end
Returns the discarded bytes when Encoding::InvalidByteSequenceError occurs.
ec = Encoding::Converter.new("EUC-JP", "ISO-8859-1") begin ec.convert("abc\xA1\xFFdef") rescue Encoding::InvalidByteSequenceError p $! #=> #<Encoding::InvalidByteSequenceError: "\xA1" followed by "\xFF" on EUC-JP> puts $!.error_bytes.dump #=> "\xA1" puts $!.readagain_bytes.dump #=> "\xFF" end
possible opt elements:
hash form: :partial_input => true # source buffer may be part of larger source :after_output => true # stop conversion after output before input integer form: Encoding::Converter::PARTIAL_INPUT Encoding::Converter::AFTER_OUTPUT
possible results:
:invalid_byte_sequence :incomplete_input :undefined_conversion :after_output :destination_buffer_full :source_buffer_empty :finished
primitive_convert converts source_buffer into destination_buffer.
source_buffer should be a string or nil. nil means an empty string.
destination_buffer should be a string.
destination_byteoffset should be an integer or nil. nil means the end of destination_buffer. If it is omitted, nil is assumed.
destination_bytesize should be an integer or nil. nil means unlimited. If it is omitted, nil is assumed.
opt should be nil, a hash or an integer. nil means no flags. If it is omitted, nil is assumed.
primitive_convert converts the content of source_buffer from beginning and store the result into destination_buffer.
destination_byteoffset and destination_bytesize specify the region which the converted result is stored. destination_byteoffset specifies the start position in destination_buffer in bytes. If destination_byteoffset is nil, destination_buffer.bytesize is used for appending the result. destination_bytesize specifies maximum number of bytes. If destination_bytesize is nil, destination size is unlimited. After conversion, destination_buffer is resized to destination_byteoffset + actually produced number of bytes. Also destination_buffer’s encoding is set to destination_encoding.
primitive_convert drops the converted part of source_buffer. the dropped part is converted in destination_buffer or buffered in Encoding::Converter object.
primitive_convert stops conversion when one of following condition met.
invalid byte sequence found in source buffer (:invalid_byte_sequence) primitive_errinfo and last_error methods returns the detail of the error.
unexpected end of source buffer (:incomplete_input) this occur only when :partial_input is not specified. primitive_errinfo and last_error methods returns the detail of the error.
character not representable in output encoding (:undefined_conversion) primitive_errinfo and last_error methods returns the detail of the error.
after some output is generated, before input is done (:after_output) this occur only when :after_output is specified.
destination buffer is full (:destination_buffer_full) this occur only when destination_bytesize is non-nil.
source buffer is empty (:source_buffer_empty) this occur only when :partial_input is specified.
conversion is finished (:finished)
example:
ec = Encoding::Converter.new("UTF-8", "UTF-16BE") ret = ec.primitive_convert(src="pi", dst="", nil, 100) p [ret, src, dst] #=> [:finished, "", "\x00p\x00i"] ec = Encoding::Converter.new("UTF-8", "UTF-16BE") ret = ec.primitive_convert(src="pi", dst="", nil, 1) p [ret, src, dst] #=> [:destination_buffer_full, "i", "\x00"] ret = ec.primitive_convert(src, dst="", nil, 1) p [ret, src, dst] #=> [:destination_buffer_full, "", "p"] ret = ec.primitive_convert(src, dst="", nil, 1) p [ret, src, dst] #=> [:destination_buffer_full, "", "\x00"] ret = ec.primitive_convert(src, dst="", nil, 1) p [ret, src, dst] #=> [:finished, "", "i"]
primitive_errinfo returns important information regarding the last error as a 5-element array:
[result, enc1, enc2, error_bytes, readagain_bytes]
result is the last result of primitive_convert.
Other elements are only meaningful when result is :invalid_byte_sequence, :incomplete_input or :undefined_conversion.
enc1 and enc2 indicate a conversion step as a pair of strings. For example, a converter from EUC-JP to ISO-8859-1 converts a string as follows: EUC-JP -> UTF-8 -> ISO-8859-1. So [enc1, enc2] is either [“EUC-JP”, “UTF-8”] or [“UTF-8”, “ISO-8859-1”].
error_bytes and readagain_bytes indicate the byte sequences which caused the error. error_bytes is discarded portion. readagain_bytes is buffered portion which is read again on next conversion.
Example:
# \xff is invalid as EUC-JP. ec = Encoding::Converter.new("EUC-JP", "Shift_JIS") ec.primitive_convert(src="\xff", dst="", nil, 10) p ec.primitive_errinfo #=> [:invalid_byte_sequence, "EUC-JP", "UTF-8", "\xFF", ""] # HIRAGANA LETTER A (\xa4\xa2 in EUC-JP) is not representable in ISO-8859-1. # Since this error is occur in UTF-8 to ISO-8859-1 conversion, # error_bytes is HIRAGANA LETTER A in UTF-8 (\xE3\x81\x82). ec = Encoding::Converter.new("EUC-JP", "ISO-8859-1") ec.primitive_convert(src="\xa4\xa2", dst="", nil, 10) p ec.primitive_errinfo #=> [:undefined_conversion, "UTF-8", "ISO-8859-1", "\xE3\x81\x82", ""] # partial character is invalid ec = Encoding::Converter.new("EUC-JP", "ISO-8859-1") ec.primitive_convert(src="\xa4", dst="", nil, 10) p ec.primitive_errinfo #=> [:incomplete_input, "EUC-JP", "UTF-8", "\xA4", ""] # Encoding::Converter::PARTIAL_INPUT prevents invalid errors by # partial characters. ec = Encoding::Converter.new("EUC-JP", "ISO-8859-1") ec.primitive_convert(src="\xa4", dst="", nil, 10, Encoding::Converter::PARTIAL_INPUT) p ec.primitive_errinfo #=> [:source_buffer_empty, nil, nil, nil, nil] # \xd8\x00\x00@ is invalid as UTF-16BE because # no low surrogate after high surrogate (\xd8\x00). # It is detected by 3rd byte (\00) which is part of next character. # So the high surrogate (\xd8\x00) is discarded and # the 3rd byte is read again later. # Since the byte is buffered in ec, it is dropped from src. ec = Encoding::Converter.new("UTF-16BE", "UTF-8") ec.primitive_convert(src="\xd8\x00\x00@", dst="", nil, 10) p ec.primitive_errinfo #=> [:invalid_byte_sequence, "UTF-16BE", "UTF-8", "\xD8\x00", "\x00"] p src #=> "@" # Similar to UTF-16BE, \x00\xd8@\x00 is invalid as UTF-16LE. # The problem is detected by 4th byte. ec = Encoding::Converter.new("UTF-16LE", "UTF-8") ec.primitive_convert(src="\x00\xd8@\x00", dst="", nil, 10) p ec.primitive_errinfo #=> [:invalid_byte_sequence, "UTF-16LE", "UTF-8", "\x00\xD8", "@\x00"] p src #=> ""
Returns an exception object for the last conversion. Returns nil if the last conversion did not produce an error.
“error” means that Encoding::InvalidByteSequenceError and Encoding::UndefinedConversionError for Encoding::Converter#convert and :invalid_byte_sequence, :incomplete_input and :undefined_conversion for Encoding::Converter#primitive_convert.
ec = Encoding::Converter.new("utf-8", "iso-8859-1") p ec.primitive_convert(src="\xf1abcd", dst="") #=> :invalid_byte_sequence p ec.last_error #=> #<Encoding::InvalidByteSequenceError: "\xF1" followed by "a" on UTF-8> p ec.primitive_convert(src, dst, nil, 1) #=> :destination_buffer_full p ec.last_error #=> nil
Returns the block length of the digest.
This method is overridden by each implementation subclass.