Function enter_scope 

pub fn enter_scope(extensions: &Extensions) -> Result<Scope, ScopeClosed>

Available on crate feature std only.

Run the input of extensions in a new scope below the scope it runs in, and attach it.

Returns that scope for the caller to hold while it serves the input. Without a scope to run in it is a new root, so every input can be ended on its own.

Errors

ScopeClosed once the scope the input runs in is closing: it admits no new work.