Class: RSX::Children

Inherits:
Object
  • Object
show all
Defined in:
lib/rsx/children.rb

Overview

The children prop of a component element.

Children compile to a block rather than a finished string, so they are rendered inside the component that received them. That is what lets <Theme.Provider> change what its children see, lets a caching component skip building them at all, and means a component that never renders children never pays for them.

The block's value is memoized, and kept in its raw form as well, so React's render-prop pattern works: { ... }.

Instance Method Summary collapse

Constructor Details

#initialize(&block) ⇒ Children

Returns a new instance of Children.



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# File 'lib/rsx/children.rb', line 18

def initialize(&block)
  @block = block
  @value = UNSET
end

Instance Method Details

#==(other) ⇒ Object 



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# File 'lib/rsx/children.rb', line 70

def ==(other)
  to_s == other.to_s
end

#call(*arguments, **options, &block) ⇒ Object

Render props: RSX::Children.childrenchildren.call(item) passes a value back to the caller.



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# File 'lib/rsx/children.rb', line 49

def call(*arguments, **options, &block)
  raw = value
  return raw.call(*arguments, **options, &block) if raw.respond_to?(:call)

  raw
end

#empty? ⇒ Boolean Also known as: blank?

Returns:

  • (Boolean) 


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# File 'lib/rsx/children.rb', line 56

def empty?
  render.empty?
end

#html_safe? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rsx/children.rb', line 44

def html_safe?
  true
end

#inspect ⇒ Object 



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# File 'lib/rsx/children.rb', line 74

def inspect
  "#<RSX::Children #{@render ? @render.inspect : "(not rendered)"}>"
end

#length ⇒ Object 



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# File 'lib/rsx/children.rb', line 66

def length
  render.length
end

#present? ⇒ Boolean Also known as: any?

Returns:

  • (Boolean) 


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# File 'lib/rsx/children.rb', line 61

def present?
  !empty?
end

#render ⇒ Object Also known as: to_rsx, to_safe_string

The rendered markup. Used whenever children are interpolated as children.



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# File 'lib/rsx/children.rb', line 30

def render
  @render ||= RSX.child(value)
end

#to_s ⇒ Object 



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# File 'lib/rsx/children.rb', line 36

def to_s
  render.to_s
end

#to_str ⇒ Object 



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# File 'lib/rsx/children.rb', line 40

def to_str
  render.to_s
end

#value ⇒ Object

The value the children expression evaluated to, before coercion.



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# File 'lib/rsx/children.rb', line 24

def value
  @value = @block.call if @value.equal?(UNSET)
  @value
end