class
   IO::Memory
 
  
  Overview
An IO that reads and writes from a buffer in memory.
The internal buffer can be resizeable and/or writeable depending
on how an IO::Memory is constructed.
Defined in:
io/memory.crConstructors
- 
        .new(capacity : Int = 64)
        
          Creates an empty, resizeable and writeable IO::Memorywith the given initial capacity for the internal buffer.
- 
        .new(string : String)
        
          Creates an IO::Memorywhose contents are the exact contents of string.
- 
        .new(slice : Bytes, writeable = true)
        
          Creates an IO::Memorythat will read, and optionally write, from/to the given slice.
Instance Method Summary
- #buffer : Pointer(UInt8)
- 
        #bytesize : Int32
        
          Same as #size.
- 
        #clear : Nil
        
          Clears the internal buffer and resets the position to zero. 
- 
        #close : Nil
        
          Closes this IO.
- 
        #closed? : Bool
        
          Determines if this IOis closed.
- 
        #empty? : Bool
        
          Returns trueif thisIO::Memoryhas no contents.
- #getb_to_end : Bytes
- #gets_to_end : String
- 
        #peek : Bytes
        
          Peeks into this IO, if possible. 
- 
        #pos : Int32
        
          Returns the current position (in bytes) of this IO.
- 
        #pos=(value)
        
          Sets the current position (in bytes) of this IO.
- 
        #read(slice : Bytes) : Int32
        
          See IO#read(slice).
- 
        #read_at(offset, bytesize, & : IO -> )
        
          Yields an IO::Memoryto read a section of thisIO's buffer.
- 
        #read_byte : UInt8 | Nil
        
          Reads a single byte from this IO.
- 
        #rewind : self
        
          Rewinds this IOto the initial position (zero).
- 
        #seek(offset, whence : Seek = Seek::Set)
        
          Seeks to a given offset (in bytes) according to the whence argument. 
- 
        #size : Int32
        
          Returns the total number of bytes in this IO.
- 
        #skip_to_end : Nil
        
          Reads and discards bytes from selfuntil there are no more bytes.
- 
        #to_s(io : IO) : Nil
        
          Appends this internal buffer to the given IO.
- 
        #to_s : String
        
          Returns a new Stringthat contains the contents of the internal buffer.
- 
        #to_slice : Bytes
        
          Returns the underlying bytes. 
- 
        #write(slice : Bytes) : Nil
        
          See IO#write(slice).
- 
        #write_byte(byte : UInt8) : Nil
        
          See IO#write_byte.
Instance methods inherited from class IO
  
  
    
      <<(obj) : self
    <<, 
    
  
    
      close
    close, 
    
  
    
      closed? : Bool
    closed?, 
    
  
    
      each_byte(&) : Nileach_byte each_byte, each_char(&) : Nil
each_char each_char, each_line(*args, **options, &block : String -> ) : Nil
each_line(*args, **options) each_line, encoding : String encoding, flush flush, getb_to_end : Bytes getb_to_end, gets(limit : Int, chomp = false) : String | Nil
gets(delimiter : Char, limit : Int, chomp = false) : String | Nil
gets(delimiter : Char, chomp = false) : String | Nil
gets(delimiter : String, chomp = false) : String | Nil
gets(chomp = true) : String | Nil gets, gets_to_end : String gets_to_end, peek : Bytes | Nil peek, pos pos, pos=(value) pos=, print(obj : _) : Nil
print(*objects : _) : Nil print, printf(format_string, args : Array | Tuple) : Nil
printf(format_string, *args) : Nil printf, puts(string : String) : Nil
puts(obj : _) : Nil
puts : Nil
puts(*objects : _) : Nil puts, read(slice : Bytes) read, read_at(offset, bytesize, & : IO -> ) read_at, read_byte : UInt8 | Nil read_byte, read_bytes(type, format : IO::ByteFormat = IO::ByteFormat::SystemEndian) read_bytes, read_char : Char | Nil read_char, read_fully(slice : Bytes) : Int32 read_fully, read_fully?(slice : Bytes) : Int32 | Nil read_fully?, read_line(*args, **options) : String read_line, read_string(bytesize : Int) : String read_string, read_utf8(slice : Bytes) read_utf8, read_utf8_byte : UInt8 | Nil read_utf8_byte, rewind rewind, seek(offset, whence : Seek = Seek::Set) seek, set_encoding(encoding : String, invalid : Symbol | Nil = nil) : Nil set_encoding, skip(bytes_count : Int) : Nil skip, skip_to_end : Nil skip_to_end, tell tell, tty? : Bool tty?, write(slice : Bytes) : Nil write, write_byte(byte : UInt8) : Nil write_byte, write_bytes(object, format : IO::ByteFormat = IO::ByteFormat::SystemEndian) : Nil write_bytes, write_string(slice : Bytes) : Nil write_string, write_utf8(slice : Bytes) : Nil write_utf8
Class methods inherited from class IO
  
  
    
      copy(src, dst, limit : Int) : Int64copy(src, dst) : Int64 copy, pipe(read_blocking = false, write_blocking = false) : Tuple(IO::FileDescriptor, IO::FileDescriptor)
pipe(read_blocking = false, write_blocking = false, &) pipe, same_content?(stream1 : IO, stream2 : IO) : Bool same_content?
Instance methods inherited from class Reference
  
  
    
      ==(other : self)==(other : JSON::Any)
==(other : YAML::Any)
==(other) ==, dup dup, hash(hasher) hash, initialize initialize, inspect(io : IO) : Nil inspect, object_id : UInt64 object_id, pretty_print(pp) : Nil pretty_print, same?(other : Reference) : Bool
same?(other : Nil) same?, to_s(io : IO) : Nil to_s
Constructor methods inherited from class Reference
  
  
    
      new
    new, 
    
  
    
      unsafe_construct(address : Pointer, *args, **opts) : self
    unsafe_construct
    
  
      
  Class methods inherited from class Reference
  
  
    
      pre_initialize(address : Pointer)
    pre_initialize
    
  
      
    
      
  Instance methods inherited from class Object
  
  
    
      ! : Bool
    !, 
    
  
    
      !=(other)
    !=, 
    
  
    
      !~(other)
    !~, 
    
  
    
      ==(other)
    ==, 
    
  
    
      ===(other : JSON::Any)===(other : YAML::Any)
===(other) ===, =~(other) =~, as(type : Class) as, as?(type : Class) as?, class class, dup dup, hash(hasher)
hash hash, in?(collection : Object) : Bool
in?(*values : Object) : Bool in?, inspect(io : IO) : Nil
inspect : String inspect, is_a?(type : Class) : Bool is_a?, itself itself, nil? : Bool nil?, not_nil!(message)
not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, responds_to?(name : Symbol) : Bool responds_to?, tap(&) tap, to_json(io : IO) : Nil
to_json : String to_json, to_pretty_json(indent : String = " ") : String
to_pretty_json(io : IO, indent : String = " ") : Nil to_pretty_json, to_s(io : IO) : Nil
to_s : String to_s, to_yaml(io : IO) : Nil
to_yaml : String to_yaml, try(&) try, unsafe_as(type : T.class) forall T unsafe_as
Class methods inherited from class Object
  
  
    
      from_json(string_or_io, root : String)from_json(string_or_io) from_json, from_yaml(string_or_io : String | IO) from_yaml
Macros inherited from class Object
  
  
    
      class_getter(*names, &block)
    class_getter, 
    
  
    
      class_getter!(*names)
    class_getter!, 
    
  
    
      class_getter?(*names, &block)
    class_getter?, 
    
  
    
      class_property(*names, &block)
    class_property, 
    
  
    
      class_property!(*names)
    class_property!, 
    
  
    
      class_property?(*names, &block)
    class_property?, 
    
  
    
      class_setter(*names)
    class_setter, 
    
  
    
      def_clone
    def_clone, 
    
  
    
      def_equals(*fields)
    def_equals, 
    
  
    
      def_equals_and_hash(*fields)
    def_equals_and_hash, 
    
  
    
      def_hash(*fields)
    def_hash, 
    
  
    
      delegate(*methods, to object)
    delegate, 
    
  
    
      forward_missing_to(delegate)
    forward_missing_to, 
    
  
    
      getter(*names, &block)
    getter, 
    
  
    
      getter!(*names)
    getter!, 
    
  
    
      getter?(*names, &block)
    getter?, 
    
  
    
      property(*names, &block)
    property, 
    
  
    
      property!(*names)
    property!, 
    
  
    
      property?(*names, &block)
    property?, 
    
  
    
      setter(*names)
    setter
    
  
    
  Constructor Detail
Creates an empty, resizeable and writeable IO::Memory with the given
initial capacity for the internal buffer.
io = IO::Memory.new
slice = Bytes.new(1)
io.pos         # => 0
io.read(slice) # => 0
slice          # => Bytes[0]Creates an IO::Memory whose contents are the exact contents of string.
The created IO::Memory is non-resizeable and non-writeable.
The IO starts at position zero for reading.
io = IO::Memory.new "hello"
io.pos        # => 0
io.gets(2)    # => "he"
io.print "hi" # raises IO::ErrorCreates an IO::Memory that will read, and optionally write, from/to
the given slice. The created IO::Memory is non-resizeable.
The IO starts at position zero for reading.
slice = Slice.new(6) { |i| ('a'.ord + i).to_u8 }
io = IO::Memory.new slice, writeable: false
io.pos            # => 0
io.read(slice)    # => 6
String.new(slice) # => "abcdef"Instance Method Detail
Clears the internal buffer and resets the position to zero.
Raises if this IO::Memory is non-resizeable.
io = IO::Memory.new
io << "abc"
io.rewind
io.gets(1) # => "a"
io.clear
io.pos         # => 0
io.gets_to_end # => ""
io = IO::Memory.new "hello"
io.clear # raises IO::ErrorCloses this IO. Further operations on this IO will raise an IO::Error.
io = IO::Memory.new "hello"
io.close
io.gets_to_end # raises IO::Error (closed stream)Determines if this IO is closed.
io = IO::Memory.new "hello"
io.closed? # => false
io.close
io.closed? # => trueReturns true if this IO::Memory has no contents.
io = IO::Memory.new
io.empty? # => true
io.print "hello"
io.empty? # => falseReads the rest of this IO data as a writable Bytes.
io = IO::Memory.new Bytes[0, 1, 3, 6, 10, 15]
io.getb_to_end # => Bytes[0, 1, 3, 6, 10, 15]
io.getb_to_end # => Bytes[]Reads the rest of this IO data as a String.
io = IO::Memory.new "hello world"
io.gets_to_end # => "hello world"
io.gets_to_end # => ""Peeks into this IO, if possible.
It returns:
- nilif this IO isn't peekable at this moment or at all
- an empty slice if it is, but EOF was reached
- a non-empty slice if some data can be peeked
The returned bytes are only valid data until a next call to any method that reads from this IO is invoked.
By default this method returns nil, but IO implementations
that provide buffering or wrap other IOs should override
this method.
Returns the current position (in bytes) of this IO.
io = IO::Memory.new "hello"
io.pos     # => 0
io.gets(2) # => "he"
io.pos     # => 2Sets the current position (in bytes) of this IO.
io = IO::Memory.new "hello"
io.pos = 3
io.gets # => "lo"Yields an IO::Memory to read a section of this IO's buffer.
During the block duration self becomes read-only,
so multiple concurrent open are allowed.
Reads a single byte from this IO. Returns nil if there is no more
data to read.
io = IO::Memory.new "a"
io.read_byte # => 97
io.read_byte # => nilRewinds this IO to the initial position (zero).
io = IO::Memory.new "hello"
io.gets(2) # => "he"
io.rewind
io.gets(2) # => "he"Seeks to a given offset (in bytes) according to the whence argument.
io = IO::Memory.new("abcdef")
io.gets(3) # => "abc"
io.seek(1, IO::Seek::Set)
io.gets(2) # => "bc"
io.seek(-1, IO::Seek::Current)
io.gets(1) # => "c"Returns a new String that contains the contents of the internal buffer.
io = IO::Memory.new
io.print 1, 2, 3
io.to_s # => "123"Returns the underlying bytes.
io = IO::Memory.new
io.print "hello"
io.to_slice # => Bytes[104, 101, 108, 108, 111]See IO#write(slice). Raises if this IO::Memory is non-writeable,
or if it's non-resizeable and a resize is needed.
See IO#write_byte. Raises if this IO::Memory is non-writeable,
or if it's non-resizeable and a resize is needed.