An irb inspector

In order to create your own custom inspector there are two things you should be aware of:

Inspector uses inspect_value, or inspect_proc, for output of return values.

This also allows for an optional init+, or init_proc, which is called when the inspector is activated.

Knowing this, you can create a rudimentary inspector as follows:

irb(main):001:0> ins = IRB::Inspector.new(proc{ |v| "omg! #{v}" })
irb(main):001:0> IRB.CurrentContext.inspect_mode = ins # => omg! #<IRB::Inspector:0x007f46f7ba7d28>
irb(main):001:0> "what?" #=> omg! what?
Methods
D
I
K
N
Constants
INSPECTORS = {}
 

Default inspectors available to irb, this includes:

:pp

Using Kernel#pretty_inspect

:yaml

Using YAML.dump

:marshal

Using Marshal.dump

Class Public methods
def_inspector(key, arg=nil, &block)

Example

Inspector.def_inspector(key, init_p=nil){|v| v.inspect}
Inspector.def_inspector([key1,..], init_p=nil){|v| v.inspect}
Inspector.def_inspector(key, inspector)
Inspector.def_inspector([key1,...], inspector)
# File lib/irb/inspector.rb, line 64
def self.def_inspector(key, arg=nil, &block)
  if block_given?
    inspector = IRB::Inspector(block, arg)
  else
    inspector = arg
  end

  case key
  when Array
    for k in key
      def_inspector(k, inspector)
    end
  when Symbol
    INSPECTORS[key] = inspector
    INSPECTORS[key.to_s] = inspector
  when String
    INSPECTORS[key] = inspector
    INSPECTORS[key.intern] = inspector
  else
    INSPECTORS[key] = inspector
  end
end
keys_with_inspector(inspector)

Determines the inspector to use where inspector is one of the keys passed during inspector definition.

# File lib/irb/inspector.rb, line 54
def self.keys_with_inspector(inspector)
  INSPECTORS.select{|k,v| v == inspector}.collect{|k, v| k}
end
new(inspect_proc, init_proc = nil)

Creates a new inspector object, using the given inspect_proc when output return values in irb.

# File lib/irb/inspector.rb, line 89
def initialize(inspect_proc, init_proc = nil)
  @init = init_proc
  @inspect = inspect_proc
end
Instance Public methods
init()

Proc to call when the inspector is activated, good for requiring dependent libraries.

# File lib/irb/inspector.rb, line 96
def init
  @init.call if @init
end
inspect_value(v)

Proc to call when the input is evaluated and output in irb.

# File lib/irb/inspector.rb, line 101
def inspect_value(v)
  @inspect.call(v)
end