class BitStruct::Vector
A Vector is, like a BitStruct, a String. It retains all of the String methods, except for [], []=, and each. These methods operate on entries instead of chars. Other methods, including length and slice, are unchanged. Hence a Vector can be used directly with sockets, binary files, etc.
Note that Vector is not a subclass of BitStruct. It cannot be used in a nest declaration in a BitStruct. Instead, use the vector declaration. See BitStruct::VectorField.
Different instances of the same Vector class may have different lengths, and a single instance can change its length. The length should always be a multiple of the struct size.
Public Class Methods
Get or set the hash of default options for the class, which apply to all
fields in the entries. If h
is provided, update the default
options with that hash. Default options are inherited.
This is especially useful with the :endian => val
option.
# File lib/bit-struct/vector.rb, line 63 def default_options h = nil @default_options ||= superclass.default_options.dup if h @default_options.merge! h if @struct_class @struct_class.default_options h end end @default_options end
# File lib/bit-struct/vector.rb, line 74 def describe(*args) fmt = args[0] || BitStruct.describe_format if block_given? struct_class.describe(*args){|desc| yield desc} yield ["..."]*5 else struct_class.describe(*args) + [fmt % (["..."]*5)] end end
# File lib/bit-struct/vector.rb, line 20 def inherited cl cl.instance_eval do @struct_class = nil end end
arg
can be an integer (number of entries) or a string (binary
data, such as another Vector of the same size).
# File lib/bit-struct/vector.rb, line 99 def initialize arg # :yields: instance case arg when Integer super(struct_class.initial_value * arg) else begin super arg rescue NameError raise ArgumentError, "must be string or integer: #{arg.inspect}" end end yield self if block_given? end
Called as a class method with a single argument in a user-defined subclass to specify a particular BitStruct class to use for each entry, instead of generating an anonymous class. Called without arguments to access the struct class, generating an anonymous one if needed. The ::struct_class inherits from the ::struct_class of the parent Vector class.
# File lib/bit-struct/vector.rb, line 32 def struct_class cl = nil if cl if @struct_class warn "changing struct_class in #{self} to #{cl}" end @struct_class = cl @struct_class.default_options default_options else unless @struct_class @struct_class = self == BitStruct::Vector ? BitStruct : Class.new(superclass.struct_class) @struct_class.default_options default_options end end @struct_class end
Public Instance Methods
Get the i
-th entry. Returns a copy of the
entry. If you want to use this copy to modify the entry, you must modify
the copy and then use []= to
replace the entry with the copy.
# File lib/bit-struct/vector.rb, line 118 def [](i) sc = self.class.struct_class entry_length = sc.round_byte_length unless (0...(length / entry_length)).include? i raise ArgumentError, "index out of range: #{i}" end sc.new slice(entry_length * i, entry_length) end
Set the i
-th entry to val
.
# File lib/bit-struct/vector.rb, line 132 def []=(i,val) entry_length = struct_class_length unless (0...(length / entry_length)).include? i raise ArgumentError, "index out of range: #{i}" end unless val.length == entry_length raise ArgumentError, "wrong entry length: #{val.length} != #{entry_length}" end _old_replace_substr(entry_length * i, entry_length, val) end
Iterate over entries.
# File lib/bit-struct/vector.rb, line 149 def each entry_length = struct_class_length (length / entry_length).times do |i| yield self[i] end end
# File lib/bit-struct/vector.rb, line 172 def inspect_detailed inspect(BitStruct::DETAILED_INSPECT_OPTS) end
# File lib/bit-struct/vector.rb, line 156 def inspect_with_options(opts = BitStruct::DEFAULT_INSPECT_OPTS) if opts[:include_class] opts = opts.dup opts[:include_class] = false s = self.class.inspect + ": " else s = "" end s << entries.map{|entry| entry.inspect(opts)}.join(opts[:separator]) lb, rb = opts[:brackets] [lb, s, rb].join end
Convenience method for instances. Returns the BitStruct class that describes each entry.
# File lib/bit-struct/vector.rb, line 87 def struct_class self.class.struct_class end
Convenience method for instances. Returns the string length in bytes of each entry in the vector.
# File lib/bit-struct/vector.rb, line 93 def struct_class_length self.class.struct_class.round_byte_length end