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- Subject: Re: Does funtion & variable name lengths effect speed?
- From: Rici Lake <lua@...>
- Date: Mon, 10 Oct 2005 14:32:19 -0500
On 10-Oct-05, at 1:31 PM, Chris Marrin wrote:
Adam D. Moss wrote:
Posti Laatikko wrote:
Since lua is intepreted language i was wondering does variables &
names effect execution speed if names are long?
Nope - they're just strings which are interned and then
compared/hashed by pointer.
But technically a long string takes longer to do the initial hash,
right? So I can imagine a situation where a string must be interned at
runtime (constructed on-the-fly) and where you might see some runtime
performance issues for long strings vs. short strings.
It's hard to imagine a scenario where you're creating a string at
runtime which is not at least O(n) on the size of the string you're
creating. However, Lua's hash function only examines a maximum number
of character (*not* the first k characters, but rather k characters
spread through the string), so it is not dependent on the length of the
string. Arguably, there are more collisions with long strings as a
result of the partial hashing, but I haven't actually observed this in