gap> func := function ( )
>     Error( "oops" );
> end;
function(  ) ... end
gap> 
gap> func := SYNTAX_TREE_CODE( SYNTAX_TREE( func ) );
function(  ) ... end
gap> 
gap> func( );
Error, oops
Stack trace:
*[1] 
<function "func">( <arguments> )
 called from read-eval loop at *stdin*:8
you can 'quit;' to quit to outer loop, or
you can 'return;' to continue
brk> QUIT;
