class IO::Delimited

• IO::Delimited
• IO
• Reference
• Object

Overview

An IO that wraps another IO, and only reads up to the beginning of a specified delimiter.

This is useful for exposing part of an underlying stream to a client.

io = IO::Memory.new "abc||123"
delimited = IO::Delimited.new(io, read_delimiter: "||")

delimited.gets_to_end # => "abc"
delimited.gets_to_end # => ""
io.gets_to_end        # => "123"

Defined in:

Constructors

• .new(io : IO, read_delimiter : String, sync_close : Bool = false)

  Creates a new IO::Delimited which wraps io, and can read until the byte sequence read_delimiter (interpreted as UTF-8) is found.

• .new(io : IO, read_delimiter : Bytes, sync_close : Bool = false)

  Creates a new IO::Delimited which wraps io, and can read until the byte sequence read_delimiter is found.

Instance Method Summary

• #close : Nil

  Closes this IO.

• #closed? : Bool

  Returns true if this IO is closed.

• #peek : Bytes | Nil

  Peeks into this IO, if possible.

• #read(slice : Bytes) : Int32

  Reads at most slice.size bytes from this IO into slice.

• #read_delimiter : Slice(UInt8)
• #sync_close=(sync_close : Bool)

  If #sync_close? is true, closing this IO will close the underlying IO.

• #sync_close? : Bool

  If #sync_close? is true, closing this IO will close the underlying IO.

• #write(slice : Bytes) : Nil

  Writes the contents of slice into this IO.

Constructor Detail

Instance Method Detail

io = IO::Memory.new "hello"
slice = Bytes.new(4)
io.read(slice) # => 4
slice          # => Bytes[104, 101, 108, 108]
io.read(slice) # => 1
slice          # => Bytes[111, 101, 108, 108]
io.read(slice) # => 0

io = IO::Memory.new
slice = Bytes.new(4) { |i| ('a'.ord + i).to_u8 }
io.write(slice)
io.to_s # => "abcd"