Class: NOSJ::Lazy

Inherits:
Object
  • Object
show all
Includes:
Enumerable, Enumerable[untyped]
Defined in:
lib/nosj/lazy.rb,
sig/nosj.rbs

Overview

A lazy view of one JSON container: children resolve on first access (containers as further Lazy nodes, scalars as values, misses as nil) and are cached on the node.

Instance Method Summary collapse

Instance Method Details

#[](token) ⇒ NOSJ::Lazy, ...

Resolves one child. String and Symbol keys index objects; Integer indices index arrays (negative indices resolve to nil, as in NOSJ.dig). Containers come back as further Lazy nodes, scalars as plain Ruby values, misses as nil. Results are cached on the node.

Parameters:

  • token (String, Symbol, Integer)

Returns:



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# File 'lib/nosj/lazy.rb', line 36

def [](token)
  cache = (@children ||= {})
  cache.fetch(token) { cache[token] = __get(token) }
end

#array? ⇒ Boolean

Returns whether this node is a JSON array.

Returns:

  • (Boolean) —

    whether this node is a JSON array



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# File 'lib/nosj/lazy.rb', line 93

def array?
  __kind == :array
end

#at_pointer(pointer) ⇒ NOSJ::Lazy, ...

Resolves an RFC 6901 JSON Pointer within this node's subtree, with the same lazy/materialize behavior as #[]. Not cached.

Parameters:

  • pointer (String) —

    e.g. "/users/3/name"

Returns:



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# File 'lib/nosj/lazy.rb', line 57

def at_pointer(pointer)
  __at_pointer(pointer)
end

#dig(first, *rest) ⇒ NOSJ::Lazy, ...

Hash#dig-shaped access, fused into a single resolution: the whole path resolves in one walk of this node's bytes, no intermediate nodes. Semantics match NOSJ.dig: misses, negative indices, and steps into scalars resolve to nil. Not cached.

Parameters:

  • path (Array<String, Symbol, Integer>)
  • first (path_element)
  • rest (path_element)

Returns:



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# File 'lib/nosj/lazy.rb', line 48

def dig(first, *rest)
  __dig([first, *rest])
end

#each ⇒ self #each ⇒ Enumerator[untyped, self]

Iterates direct children, resolved in one walk: object nodes yield [key, child] pairs (like Hash), array nodes yield children. Containers arrive as Lazy nodes, scalars as values.

Overloads:

  • #each ⇒ self

    Returns:

    • (self)
  • #each ⇒ Enumerator[untyped, self]

    Returns:

    • (Enumerator[untyped, self])

Yields:

Yield Parameters:

  • arg0 (Object)

Yield Returns:

  • (void)

Returns:

  • (Enumerator) —

    when no block is given



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# File 'lib/nosj/lazy.rb', line 126

def each(&block)
  return enum_for(:each) unless block

  if object?
    __children.each { |pair| yield pair }
  else
    __children.each { |child| yield child }
  end
  self
end

#empty? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/nosj/lazy.rb', line 117

def empty?
  size.zero?
end

#inspect ⇒ String Also known as: to_s

Returns kind and span size, without touching content.

Returns:

  • (String) —

    kind and span size, without touching content



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# File 'lib/nosj/lazy.rb', line 138

def inspect
  "#<NOSJ::Lazy #{__kind} (#{__byte_size} bytes)>"
end

#keys ⇒ Array<String>

The object's keys (always Strings), read in one walk without materializing any values.

Returns:

  • (Array<String>)

Raises:

  • (TypeError) —

    on an array node



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# File 'lib/nosj/lazy.rb', line 102

def keys
  __keys
end

#object? ⇒ Boolean

Returns whether this node is a JSON object.

Returns:

  • (Boolean) —

    whether this node is a JSON object



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# File 'lib/nosj/lazy.rb', line 88

def object?
  __kind == :object
end

#size ⇒ Integer Also known as: length, count

Entry count (object pairs or array elements), read in one walk without materializing anything.

Returns:

  • (Integer) 


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# File 'lib/nosj/lazy.rb', line 110

def size
  __size
end

#to_a ⇒ Array

Returns the materialized subtree.

Returns:

  • (Array) —

    the materialized subtree

Raises:

  • (TypeError) —

    on an object node



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# File 'lib/nosj/lazy.rb', line 81

def to_a
  raise TypeError, "to_a on a JSON object" unless array?

  __materialize
end

#to_h ⇒ Hash

Returns the materialized subtree.

Returns:

  • (Hash) —

    the materialized subtree

Raises:

  • (TypeError) —

    on an array node



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# File 'lib/nosj/lazy.rb', line 73

def to_h
  raise TypeError, "to_h on a JSON array" unless object?

  __materialize
end

#value ⇒ Hash, Array Also known as: materialize

Materializes this node's whole subtree as plain Ruby values, under the options given to NOSJ.lazy (+symbolize_names+, freeze, ...).

Returns:

  • (Hash, Array) 


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# File 'lib/nosj/lazy.rb', line 66

def value
  __materialize
end