Macro sapio::then

macro_rules! then {
    {
        $(#[$meta:meta])*
        $name:ident $a:tt |$s:ident, $ctx:ident| $b:block } => { ... };
    {
        $(#[$meta:meta])*
        $name:ident |$s:ident, $ctx:ident| $b:block } => { ... };
    {
        $(#[$meta:meta])*
        $name:ident} => { ... };
}

The then macro is used to define a ThenFunc formats for calling are:

/// A Guarded CTV Function
then!(name [guard_1, ... guard_n] |s| {/*Result<Box<Iterator<TransactionTemplate>>>*/} );
/// An Unguarded CTV Function
then!(name |s| {/*Result<Box<Iterator<TransactionTemplate>>>*/} );
/// Null Implementation
then!(name);