Interpolate Regexp expression.

gistfile1.txt

{
 ["/home/guoxiang/work/rails-dev-box/rails/actionpack/lib/action_controller/metal/test.rb", 8, :T_ARRAY]=>[1, 0, 0, 0, 0, 0],
 ["/home/guoxiang/work/rails-dev-box/rails/actionpack/lib/action_controller/metal/test.rb", 8, :T_STRING]=>[6, 0, 0, 0, 0, 0],
 ["/home/guoxiang/work/rails-dev-box/rails/actionpack/lib/action_controller/metal/test.rb", 8, :T_REGEXP]=>[1, 0, 0, 0, 0, 0]
}

test.rb

require 'objspace'
require 'allocation_tracer'
require 'pp'

ObjectSpace::AllocationTracer.setup(%i{path line type})
a = "asd"
result = ObjectSpace::AllocationTracer.trace do
  /#{a}/
end

pp result