-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 05/30/11 15:00, Matthew Flatt wrote: > How would `hash-empty?' be different than `hash-count' for a weak hash > table? A traversal of the table is needed to check whether any keys > have disappeared.
But as soon as an non-disappeared key has been found `hash-empty?' could return without needing to traverse the rest of the table. > That is, I don't see how to make `hash-empty?' on a > weak table a constant-time operation without additional GC support. It might not be possible to make `hash-empty?' a constant-time operation, but in a big table the difference between traversing until the first non-disappeared key and traversing the complete table would still be significant, wouldn't it? Marijn -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.17 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk3jotMACgkQp/VmCx0OL2wqcgCgoS6P8HXcR5hIUI9bZpg79mqr N2wAmwZ2p0uaLI8XjmYGb8zvaw8FSdbh =Q4Wm -----END PGP SIGNATURE----- _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
