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/Ruby 4.0

module PP::PPMethods

Module that defines helper methods for pretty_print.

Public Instance Methods

# File lib/pp.rb, line 161
def check_inspect_key(id)
  recursive_state = Thread.current[:__recursive_key__] or return false
  recursive_state[:inspect]&.include?(id)
end

check_inspect_key (id) Show source

Check whether the object_id id is in the current buffer of objects to be pretty printed. Used to break cycles in chains of objects to be pretty printed.

# File lib/pp.rb, line 238
def comma_breakable
  text ','
  breakable
end

comma_breakable () Show source

A convenience method which is same as follows:

text ','
breakable

# File lib/pp.rb, line 147
def guard_inspect_key
  recursive_state = Thread.current[:__recursive_key__] ||= {}.compare_by_identity
  save = recursive_state[:inspect] ||= {}.compare_by_identity
  begin
    recursive_state[:inspect] = {}.compare_by_identity
    yield
  ensure
    recursive_state[:inspect] = save
  end
end

guard_inspect_key () { || ... } Show source

Yields to a block and preserves the previous set of objects being printed.

# File lib/pp.rb, line 228
def object_address_group(obj, &block)
  str = Kernel.instance_method(:to_s).bind_call(obj)
  str.chomp!('>')
  group(1, str, '>', &block)
end

object_address_group (obj, &block) Show source

A convenience method, like object_group, but also reformats the Object’s object_id.

# File lib/pp.rb, line 222
def object_group(obj, &block) # :yield:
  group(1, '#<' + obj.class.name, '>', &block)
end

object_group (obj) { || ... } Show source

A convenience method which is same as follows:

group(1, '#<' + obj.class.name, '>') { ... }

# File lib/pp.rb, line 173
def pop_inspect_key(id)
  Thread.current[:__recursive_key__][:inspect].delete id
end

pop_inspect_key (id) Show source

Removes an object from the set of objects being pretty printed.

# File lib/pp.rb, line 200
def pp(obj)
  # If obj is a Delegator then use the object being delegated to for cycle
  # detection
  obj = obj.__getobj__ if defined?(::Delegator) and ::Delegator === obj

  if check_inspect_key(obj)
    group {obj.pretty_print_cycle self}
    return
  end

  guard_inspect(obj) do
    group do
      obj.pretty_print self
    rescue NoMethodError
      text Kernel.instance_method(:inspect).bind_call(obj)
    end
  end
end

pp (obj) Show source

Adds obj to the pretty printing buffer using Object#pretty_print or Object#pretty_print_cycle.

Object#pretty_print_cycle is used when obj is already printed, a.k.a the object reference chain has a cycle.

# File lib/pp.rb, line 302
def pp_hash(obj)
  group(1, '{', '}') {
    seplist(obj, nil, :each_pair) {|k, v|
      group {
        pp_hash_pair k, v
      }
    }
  }
end

pp_hash (obj) Show source

A pretty print for a Hash

# File lib/pp.rb, line 314
def pp_hash_pair(k, v)
  if Symbol === k
    if k.inspect.match?(%r[\A:["$@!]|[%&*+\-\/<=>@\]^`|~]\z])
      k = k.to_s.inspect
    end
    text "#{k}:"
  else
    pp k
    text ' '
    text '=>'
  end
  group(1) {
    breakable
    pp v
  }
end

pp_hash_pair (k, v) Show source

A pretty print for a pair of Hash

# File lib/pp.rb, line 286
def pp_object(obj)
  object_address_group(obj) {
    seplist(obj.pretty_print_instance_variables, lambda { text ',' }) {|v|
      breakable
      v = v.to_s if Symbol === v
      text v
      text '='
      group(1) {
        breakable ''
        pp(obj.instance_eval(v))
      }
    }
  }
end

pp_object (obj) Show source

A present standard failsafe for pretty printing any given Object

# File lib/pp.rb, line 168
def push_inspect_key(id)
  Thread.current[:__recursive_key__][:inspect][id] = true
end

push_inspect_key (id) Show source

Adds the object_id id to the set of objects being pretty printed, so as to not repeat objects.

# File lib/pp.rb, line 267
def seplist(list, sep=nil, iter_method=:each) # :yield: element
  sep ||= lambda { comma_breakable }
  first = true
  kwsplat = EMPTY_KWHASH
  list.__send__(iter_method) {|*v|
    if first
      first = false
    else
      sep.call
    end
    kwsplat ? yield(*v, **kwsplat) : yield(*v)
  }
end

seplist (list, sep=nil, iter_method=:each) { |element| ... } Show source

Adds a separated list. The list is separated by comma with breakable space, by default.

seplist iterates the list using iter_method. It yields each object to the block given for seplist. The procedure separator_proc is called between each yields.

If the iteration is zero times, separator_proc is not called at all.

If separator_proc is nil or not given, +lambda { comma_breakable }+ is used. If iter_method is not given, :each is used.

For example, following 3 code fragments has similar effect.

q.seplist([1,2,3]) {|v| xxx v }

q.seplist([1,2,3], lambda { q.comma_breakable }, :each) {|v| xxx v }

xxx 1
q.comma_breakable
xxx 2
q.comma_breakable
xxx 3

Ruby Core © 1993–2025 Yukihiro Matsumoto
Licensed under the Ruby License.
Ruby Standard Library © contributors
Licensed under their own licenses.