Macro combu::check

macro_rules! check {
    (error) => { ... };
    (error, $($t:tt)*) => { ... };
    (help, $cmd:ident, $ctx:ident) => { ... };
    (help,$cmd:ident,$ctx:ident,$func:path) => { ... };
    (license,$cmd:ident,$ctx:ident) => { ... };
    ($member:ident,$cmd:ident,$ctx:ident) => { ... };
    ($member:ident,$cmd:ident,$ctx:ident,$func:path) => { ... };
    ($member:ident,$cmd:ident,$ctx:ident,{$($t:tt)*}) => { ... };
}

Checks context macro.