>
<p><code>allow_not_macro</code>:</p>
<p>By default, the attribute checks that it's applied to a proc-macro.
If none of <code>#[proc_macro]</code>, <code>#[proc_macro_derive]</code> nor <code>#[proc_macro_attribute]</code> are
present it will panic. It's the intention - this crate is supposed to be used only with
proc-macros.</p>
<p>This setting is made to bypass the check, useful in certain circumstances.</p>
<p>Please note: the function this attribute is applied to must return
<code>proc_macro::TokenStre