16 x 8 = 128  (i.e. > 64)

With 

...
for (0..16) {
    my $value = vec($mask,$_,8);
    print "$value\n";
}

[download]

I do get (as expected): 

255
255
255
255
255
255
255
255
0
0
0
0
0
0
0
0
0

[download]

In other words, the offset is in units as specified in width (8 bits here).

In reply to Re: how does vec() return? by almut
in thread how does vec() return? by llancet

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