class Concurrent::ThreadLocalVar
@!macro [attach] thread_local_var
A `ThreadLocalVar` is a variable where the value is different for each thread.
Each variable may have a default value, but when you modify the variable only
the current thread will ever see that change.
@!macro thread_safe_variable_comparison
@example
v = ThreadLocalVar.new(14)
v.value #=> 14
v.value = 2
v.value #=> 2
@example
v = ThreadLocalVar.new(14)
t1 = Thread.new do
v.value #=> 14
v.value = 1
v.value #=> 1
end
t2 = Thread.new do
v.value #=> 14
v.value = 2
v.value #=> 2
end
v.value #=> 14
@see https://docs.oracle.com/javase/7/docs/api/java/lang/ThreadLocal.html Java ThreadLocal
@!macro thread_local_var_public_api