Convert source_string and return destination_string.
source_string is assumed as a part of source. i.e. :partial_input=>true is specified internally. finish method should be used last.
ec = Encoding::Converter.new("utf-8", "euc-jp") puts ec.convert("\u3042").dump #=> "\xA4\xA2" puts ec.finish.dump #=> "" ec = Encoding::Converter.new("euc-jp", "utf-8") puts ec.convert("\xA4").dump #=> "" puts ec.convert("\xA2").dump #=> "\xE3\x81\x82" puts ec.finish.dump #=> "" ec = Encoding::Converter.new("utf-8", "iso-2022-jp") puts ec.convert("\xE3").dump #=> "".force_encoding("ISO-2022-JP") puts ec.convert("\x81").dump #=> "".force_encoding("ISO-2022-JP") puts ec.convert("\x82").dump #=> "\e$B$\"".force_encoding("ISO-2022-JP") puts ec.finish.dump #=> "\e(B".force_encoding("ISO-2022-JP")
If a conversion error occur, Encoding::UndefinedConversionError
or Encoding::InvalidByteSequenceError
is raised. Encoding::Converter#convert
doesn’t supply methods to recover or restart from these exceptions. When you want to handle these conversion errors, use Encoding::Converter#primitive_convert
.
Creates a class to wrap the C union described by signature
.
MyUnion = union ['int i', 'char c']
Start streaming using encoding
Set
all the parameters.
Parses self
destructively and returns self
containing the rest arguments left unparsed.
Returns collection of supported maker versions
Executes the passed block and raises exception
if execution takes more than seconds
.
If seconds
is zero or nil, simply executes the block
Executes the passed block and raises exception
if execution takes more than seconds
.
If seconds
is zero or nil, simply executes the block
Tries to convert obj
into an array, using to_ary
method. Returns the converted array or nil
if obj
cannot be converted for any reason. This method can be used to check if an argument is an array.
Array.try_convert([1]) #=> [1] Array.try_convert("1") #=> nil if tmp = Array.try_convert(arg) # the argument is an array elsif tmp = String.try_convert(arg) # the argument is a string end
Returns the factorization of self
.
See Prime#prime_division
for more details.
Try to convert obj into a String, using to_str
method. Returns converted string or nil if obj cannot be converted for any reason.
String.try_convert("str") #=> "str" String.try_convert(/re/) #=> nil
Converts a pathname to an absolute pathname. Relative paths are referenced from the current working directory of the process unless dir_string
is given, in which case it will be used as the starting point. The given pathname may start with a “~
”, which expands to the process owner’s home directory (the environment variable HOME
must be set correctly). “~
user” expands to the named user’s home directory.
File.expand_path("~oracle/bin") #=> "/home/oracle/bin"
A simple example of using dir_string
is as follows.
File.expand_path("ruby", "/usr/bin") #=> "/usr/bin/ruby"
A more complex example which also resolves parent directory is as follows. Suppose we are in bin/mygem and want the absolute path of lib/mygem.rb.
File.expand_path("../../lib/mygem.rb", __FILE__) #=> ".../path/to/project/lib/mygem.rb"
So first it resolves the parent of __FILE__, that is bin/, then go to the parent, the root of the project and appends lib/mygem.rb
.
Duplicates self and resets its day of calendar reform.
d = Date.new(1582,10,15) d.new_start(Date::JULIAN) #=> #<Date: 1582-10-05 ...>
Returns a Time
object which denotes self.
Returns a DateTime
object which denotes self.
Returns a Time
object which denotes self.
Returns self.
Returns self.
Returns a DateTime
object which denotes self.
Waits until IO
is writable without blocking and returns self
or nil
when times out.
Try to convert obj into an IO
, using to_io
method. Returns converted IO
or nil
if obj cannot be converted for any reason.
IO.try_convert(STDOUT) #=> STDOUT IO.try_convert("STDOUT") #=> nil require 'zlib' f = open("/tmp/zz.gz") #=> #<File:/tmp/zz.gz> z = Zlib::GzipReader.open(f) #=> #<Zlib::GzipReader:0x81d8744> IO.try_convert(z) #=> #<File:/tmp/zz.gz>
Writes the given string to ios using the write(2) system call after O_NONBLOCK is set for the underlying file descriptor.
It returns the number of bytes written.
write_nonblock
just calls the write(2) system call. It causes all errors the write(2) system call causes: Errno::EWOULDBLOCK, Errno::EINTR, etc. The result may also be smaller than string.length (partial write). The caller should care such errors and partial write.
If the exception is Errno::EWOULDBLOCK or Errno::EAGAIN, it is extended by IO::WaitWritable
. So IO::WaitWritable
can be used to rescue the exceptions for retrying write_nonblock.
# Creates a pipe. r, w = IO.pipe # write_nonblock writes only 65536 bytes and return 65536. # (The pipe size is 65536 bytes on this environment.) s = "a" * 100000 p w.write_nonblock(s) #=> 65536 # write_nonblock cannot write a byte and raise EWOULDBLOCK (EAGAIN). p w.write_nonblock("b") # Resource temporarily unavailable (Errno::EAGAIN)
If the write buffer is not empty, it is flushed at first.
When write_nonblock
raises an exception kind of IO::WaitWritable
, write_nonblock
should not be called until io is writable for avoiding busy loop. This can be done as follows.
begin result = io.write_nonblock(string) rescue IO::WaitWritable, Errno::EINTR IO.select(nil, [io]) retry end
Note that this doesn’t guarantee to write all data in string. The length written is reported as result and it should be checked later.
On some platforms such as Windows, write_nonblock
is not supported according to the kind of the IO
object. In such cases, write_nonblock
raises Errno::EBADF
.
By specifying a keyword argument exception to false
, you can indicate that write_nonblock
should not raise an IO::WaitWritable
exception, but return the symbol :wait_writable
instead.