Macro suffix 

macro_rules! suffix {
    (
		{$map:path}
		($($suffix:tt)*)
		[$(,)? {$($next:tt)*} $($rest:tt)*]
	) => { ... };
    (
		($($suffix:tt)*)
		[$(,)? {$($next:tt)*} $($rest:tt)*]
	) => { ... };
    (
		$({$map:path})?
		($($suffix:tt)*)
		[$(,)?]
	) => { ... };
}

Suffixes tokens to groups of other tokens.

Optionally, a mapping macro can be provided to transform each resulting suffixed token group.

suffix! {
	(foo)
	[{bar 1}, {baz 2}, {qux 3}]
}

// Expands to:
// bar 1 foo
// baz 2 foo
// qux 3 foo

With mapping macro:

macro_rules! wrap_in_parens {
	($($tokens:tt)*) => {
		( $($tokens)* )
	};
}

suffix! {
	{wrap_in_parens}
	(foo)
	[{bar 1}, {baz 2}, {qux 3}]
}

// Expands to:
// ( bar 1 foo )
// ( baz 2 foo )
// ( qux 3 foo )