djb2.tcl

proc djb2 { {input ""} {result 5381} } {

	foreach c [split $input ""] {
		set result [expr {($result << 5) + $result + [scan $c %c] & 0xFFFFFFFF}]
	}
	
	return $result
}

proc bench1 {} {djb2 "ANOLPMAP447568116268"}
proc bench2 {} {djb2 "447568116268" 2860308605}

# Full hash using the salt
puts [djb2 "ANOLPMAP447568116268"]
# Optimized hash with the precomputed salt
puts [djb2 "447568116268" 2860308605]

puts [time {bench1} 1000]
puts [time {bench2} 1000]

Does it make sense to replace the switch (which looks it might involve ugly string comparisons) with a Tcl list?

set t {48 49 50 51 52 53 54 55 56 57}
set ord [lindex $t $c]

Or, going one step ahead, "abusing" the fact that it's continuous:

set ord = $c + 48

might be slightly faster. I don't know jack about Tcl, but I'm used to the fact that switch is a terrible operation for the cpu as it's usually implemented as a bunch of branches that screw up with the branch predictor, so I followed the mantra to try to stay out of switch. Might be completely wrong in the context of Tcl. Or maybe it's not in the part consuming the most % of cpu and it's not relevant.

These will fail miserably if we don't have numbers, ofc, but I don't know if this is really an issue or not. I don't know if the + will be an issue neither.