Expunge pretends to be a cover function that can be called instead of ⎕EX, but it does not return the same result as ⎕EX does.
⎕EX returns a 1 for a name that is now available. It does not report success or failure of the delete operation:
a←1
⊢⎕EX 'a'
1
⊢⎕EX 'a'
1
⊢⎕EX '1a'
0
The Expunge function does not say anything about its result but from the code I can tell that it attempts (at least in one place) to report success:
:If 0=nc
r[i]←0
:Continue
:EndIf
But it does not do that consistently, see #506 ("Expunge does not deal correctly with ## and the likes").
Expected behaviour
Either return the same result as ⎕EX or (my preference) return an indicator that the delete was successfully performed on the file because deleting it from the WS should always succeed anyway.
Returning the same result as ⎕EX does seem to be pretty pointless: I was never able to put this to good use in decades. Also, hardly anybody knows what the result of ⎕EX actually means.
Expungepretends to be a cover function that can be called instead of⎕EX, but it does not return the same result as⎕EXdoes.⎕EXreturns a 1 for a name that is now available. It does not report success or failure of the delete operation:The
Expungefunction does not say anything about its result but from the code I can tell that it attempts (at least in one place) to report success:But it does not do that consistently, see #506 ("Expunge does not deal correctly with ## and the likes").
Expected behaviour
Either return the same result as
⎕EXor (my preference) return an indicator that the delete was successfully performed on the file because deleting it from the WS should always succeed anyway.Returning the same result as
⎕EXdoes seem to be pretty pointless: I was never able to put this to good use in decades. Also, hardly anybody knows what the result of⎕EXactually means.