Is it possible to store a variable like in Capture but make it available everywhere in the parent scope?

How can I create a Block tag that behaves like a Capture tag, but I want it to be available anywhere in the calling template, not ONLY after it.

For example, the Capture tag looks like:

class Capture < Block
    Syntax = /(#{VariableSignature}+)/o

    def initialize(tag_name, markup, options)
      super
      if markup =~ Syntax
        @to = $1
      else
        raise SyntaxError.new(options[:locale].t("errors.syntax.capture"))
      end
    end

    def render(context)
      output = super
      context.scopes.last[@to] = output
      context.resource_limits.assign_score += output.length
      ''.freeze
    end

    def blank?
      true
    end
  end

And it currently works like:

{% capture heading %}
       Monkeys!
 {% endcapture %}
 
<h1>{{ heading }}</h1>

If you put {{heading}} before the definition of the variable, it doesn't work. Is it possible to make it work even BEFORE the definition? Somehow put the variable in the parent scope?

The issue provides a Capture implementation based on Block#render and context.scopes.last, but names no repository file or test. Start by tracing how Capture assigns its value and how template variable lookup handles scope and ordering; done requires a maintainer-approved design and coverage for the requested before-definition behavior.