The Rakudo implementation of Raku tracks multiple issues about the (very useful!) &?ROUTINE variable not providing the correct value (e.g., #1768 and 2362), so I realize that it's not behaving quite correctly. But I'm trying to understand what it's intended behavior is – which seems like an essential first step in fixing that behavior.

Running this code with Rakudo v2021.06 produces the output noted in the comments. Which parts of this output are correct, and which represent bugs?

sub foo  {
    note '## ifs:';
    do if True { say &?ROUTINE.name }                # OUTPUT: «foo»
    if True    { say &?ROUTINE.name }                # OUTPUT: «<unit>»

    note '## ifs w/ topic:';
    do if True -> $a { say $a; say &?ROUTINE.name }  # OUTPUT: «True», # OUTPUT«""»
    if True -> $a    { say $a; say &?ROUTINE.name }  # OUTPUT: «True», # OUTPUT«foo»
    
    note '## fors:';
    for 1 { say &?ROUTINE.name }                     # OUTPUT: «foo»
    say &?ROUTINE.name for 1;                        # OUTPUT: «""»

    note '## methods:';
    42.&{              say &?ROUTINE.name }          # OUTPUT: «foo»
    my method m($a:) { say &?ROUTINE.name }
    42.&m;                                           # OUTPUT: «m»
}
foo 

The relevant docs say that &?ROUTINE returns "an instance of Sub", which makes it sound like all of the above should be 'foo'. On the other hand, a Method is a Routine, so I'm somewhat inclined to think that the last two (an anonymous method and a named method) should not be 'foo'. I'm also unsure whether all the '' and "" values represent bugs, or if there's a principle at work that makes some (or all?) of those intended behavior.

(I also tested the above code with the use soft pragma to make sure that inlining wasn't having an effect that I could fix with that pragma; it had no effect on the output)

回答

sub foo  {
    note '## ifs:';
    do if True { say &?ROUTINE.name }                # OUTPUT: «foo»
    if True    { say &?ROUTINE.name }                # OUTPUT: «foo»

    note '## ifs w/ topic:';
    do if True -> $a { say $a; say &?ROUTINE.name }  # OUTPUT: «True», # OUTPUT«foo»
    if True -> $a    { say $a; say &?ROUTINE.name }  # OUTPUT: «True», # OUTPUT«foo»
    
    note '## fors:';
    for 1 { say &?ROUTINE.name }                     # OUTPUT: «foo»
    say &?ROUTINE.name for 1;                        # OUTPUT: «foo»

    note '## methods:';
    42.&{              say &?ROUTINE.name }          # OUTPUT: «foo»
    my method m($a:) { say &?ROUTINE.name }
    42.&m;                                           # OUTPUT: «m»
}
foo 

回答