[type]
CompositeParser

[grammar]
grammar M; // uses no rules from the import
import S;
s : 'b' {<Invoke_foo()>} ; // gS is import pointer
WS : (' '|'\n') -> skip ;

[slaveGrammar]
parser grammar S;
@parser::members {
<Declare_foo()>
}
a : B;

[start]
s

[input]
b

[output]
"""foo
"""