Class: BinData::BasePrimitive
- Defined in:
- lib/bindata/base_primitive.rb,
lib/bindata/trace.rb
Overview
A BinData::BasePrimitive object is a container for a value that has a particular binary representation. A value corresponds to a primitive type such as as integer, float or string. Only one value can be contained by this object. This value can be read from or written to an IO stream.
require 'bindata'
obj = BinData::Uint8.new(:initial_value => 42)
obj #=> 42
obj.assign(5)
obj #=> 5
obj.clear
obj #=> 42
obj = BinData::Uint8.new(:value => 42)
obj #=> 42
obj.assign(5)
obj #=> 42
obj = BinData::Uint8.new(:check_value => 3)
obj.read("\005") #=> BinData::ValidityError: value is '5' but expected '3'
obj = BinData::Uint8.new(:check_value => lambda { value < 5 })
obj.read("\007") #=> BinData::ValidityError: value not as expected
Parameters
Parameters may be provided at initialisation to control the behaviour of an object. These params include those for BinData::Base as well as:
:initial_value
-
This is the initial value to use before one is either #read or explicitly set with #value=.
:value
-
The object will always have this value. Calls to #value= are ignored when using this param. While reading, #value will return the value of the data read from the IO, not the result of the
:value
param. :assert
-
Raise an error unless the value read or assigned meets this criteria. The variable
value
is made available to any lambda assigned to this parameter. A boolean return indicates success or failure. Any other return is compared to the value just read in. :asserted_value
-
Equavalent to
:assert
and:value
.
Direct Known Subclasses
CountBytesRemaining, DoubleBe, DoubleLe, FloatBe, FloatLe, Int8, Primitive, Rest, Skip, String, Stringz, Uint8
Defined Under Namespace
Modules: AssertPlugin, AssertedValuePlugin, CheckValuePlugin, InitialValuePlugin, ValuePlugin
Instance Attribute Summary
Attributes inherited from Base
Class Method Summary collapse
Instance Method Summary collapse
- #<=>(other) ⇒ Object
- #assign(val) ⇒ Object (also: #value=)
-
#clear? ⇒ Boolean
:nodoc:.
-
#do_num_bytes ⇒ Object
:nodoc:.
-
#do_read(io) ⇒ Object
:nodoc:.
- #do_read_with_hook(io) ⇒ Object
-
#do_write(io) ⇒ Object
:nodoc:.
- #eql?(other) ⇒ Boolean
- #hash ⇒ Object
- #initialize_instance ⇒ Object
- #initialize_shared_instance ⇒ Object
-
#method_missing(symbol, *args, &block) ⇒ Object
:nodoc:.
-
#respond_to?(symbol, include_private = false) ⇒ Boolean
:nodoc:.
- #snapshot ⇒ Object
- #trace_value ⇒ Object
- #value ⇒ Object
Methods inherited from Base
#==, #=~, arg_extractor, bindata_name, #clear, #debug_name, #eval_parameter, #get_parameter, #has_parameter?, #initialize_with_warning, #inspect, #lazy_evaluator, #new, #num_bytes, #offset, #pretty_print, #read, read, register_subclasses, #rel_offset, #safe_respond_to?, #to_binary_s, #to_s, unregister_self, #write
Methods included from AcceptedParametersPlugin
#accepted_parameters, #default_parameters, #mandatory_parameters, #mutually_exclusive_parameters, #optional_parameters
Methods included from RegisterNamePlugin
Methods included from CheckOrAdjustOffsetPlugin
Methods included from Framework
#debug_name_of, included, #offset_of
Dynamic Method Handling
This class handles dynamic methods through the method_missing method
#method_missing(symbol, *args, &block) ⇒ Object
:nodoc:
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# File 'lib/bindata/base_primitive.rb', line 107 def method_missing(symbol, *args, &block) #:nodoc: child = snapshot if child.respond_to?(symbol) child.__send__(symbol, *args, &block) else super end end |
Class Method Details
.bit_aligned ⇒ Object
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# File 'lib/bindata/alignment.rb', line 71 def BasePrimitive.bit_aligned include BitAligned end |
.turn_off_tracing ⇒ Object
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# File 'lib/bindata/trace.rb', line 52 def turn_off_tracing alias_method :do_read, :do_read_without_hook end |
.turn_on_tracing ⇒ Object
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# File 'lib/bindata/trace.rb', line 47 def turn_on_tracing alias_method :do_read_without_hook, :do_read alias_method :do_read, :do_read_with_hook end |
Instance Method Details
#<=>(other) ⇒ Object
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# File 'lib/bindata/base_primitive.rb', line 116 def <=>(other) snapshot <=> other end |
#assign(val) ⇒ Object Also known as: value=
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# File 'lib/bindata/base_primitive.rb', line 81 def assign(val) raise ArgumentError, "can't set a nil value for #{debug_name}" if val.nil? raw_val = val.respond_to?(:snapshot) ? val.snapshot : val @value = begin raw_val.dup rescue TypeError # can't dup Fixnums raw_val end end |
#clear? ⇒ Boolean
:nodoc:
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# File 'lib/bindata/base_primitive.rb', line 77 def clear? #:nodoc: @value.nil? end |
#do_num_bytes ⇒ Object
:nodoc:
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# File 'lib/bindata/base_primitive.rb', line 137 def do_num_bytes #:nodoc: value_to_binary_string(_value).length end |
#do_read(io) ⇒ Object
:nodoc:
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# File 'lib/bindata/base_primitive.rb', line 129 def do_read(io) #:nodoc: @value = read_and_return_value(io) end |
#do_read_with_hook(io) ⇒ Object
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# File 'lib/bindata/trace.rb', line 57 def do_read_with_hook(io) do_read_without_hook(io) trace_value end |
#do_write(io) ⇒ Object
:nodoc:
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# File 'lib/bindata/base_primitive.rb', line 133 def do_write(io) #:nodoc: io.writebytes(value_to_binary_string(_value)) end |
#eql?(other) ⇒ Boolean
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# File 'lib/bindata/base_primitive.rb', line 120 def eql?(other) # double dispatch other.eql?(snapshot) end |
#hash ⇒ Object
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# File 'lib/bindata/base_primitive.rb', line 125 def hash snapshot.hash end |
#initialize_instance ⇒ Object
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# File 'lib/bindata/base_primitive.rb', line 73 def initialize_instance @value = nil end |
#initialize_shared_instance ⇒ Object
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# File 'lib/bindata/base_primitive.rb', line 58 def initialize_shared_instance if has_parameter?(:check_value) and has_parameter?(:value) warn ":check_value has been deprecated. Consider using :asserted_value instead of :check_value and :value in #{self.class}." elsif has_parameter?(:check_value) warn ":check_value has been deprecated. Use :assert instead in #{self.class}." end extend InitialValuePlugin if has_parameter?(:initial_value) extend ValuePlugin if has_parameter?(:value) extend CheckValuePlugin if has_parameter?(:check_value) extend AssertPlugin if has_parameter?(:assert) extend AssertedValuePlugin if has_parameter?(:asserted_value) super end |
#respond_to?(symbol, include_private = false) ⇒ Boolean
:nodoc:
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# File 'lib/bindata/base_primitive.rb', line 102 def respond_to?(symbol, include_private = false) #:nodoc: child = snapshot child.respond_to?(symbol, include_private) || super end |
#snapshot ⇒ Object
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# File 'lib/bindata/base_primitive.rb', line 93 def snapshot _value end |
#trace_value ⇒ Object
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# File 'lib/bindata/trace.rb', line 62 def trace_value BinData:: do |tracer| value_string = _value.inspect tracer.trace_obj(debug_name, value_string) end end |
#value ⇒ Object
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# File 'lib/bindata/base_primitive.rb', line 97 def value snapshot end |