[REBOL] Re: Best way to remove the last character from a string?
From: cyphre:seznam:cz at: 15-Dec-2004 8:21
Hi all,
I made simple performace measurement of a few methods with the same effect:
--------------<begin code>--------------
profile: func [
blk n
/local st
][
st: now/time/precise
loop n blk
print [n "cycles took" now/time/precise - st]
]
methods: [
[mystring: "123456" mystring: head remove back tail mystring]
[mystring: "123456" mystring: copy/part mystring ((length? mystring) - 1)]
[mystring: "123456" copy/part mystring ((length? mystring) - 1)]
[mystring: "123456" copy/part mystring skip tail mystring -1]
[mystring: "123456" copy/part mystring at tail mystring -1]
[mystring: "123456" mystring: head reverse remove head reverse mystring]
[mystring: "123456" mystring: head remove at mystring length? mystring]
]
foreach m methods [
print ["measuring method:" mold m]
profile m 10'000'000
]
--------------<end code>--------------
results on my machine:
measuring method: [mystring: "123456" mystring: head remove back tail
mystring]
10000000 cycles took 0:00:11.953
measuring method: [mystring: "123456" mystring: copy/part mystring ((length?
mystring) - 1)]
10000000 cycles took 0:00:17.407
measuring method: [mystring: "123456" copy/part mystring ((length?
mystring) - 1)]
10000000 cycles took 0:00:16.406
measuring method: [mystring: "123456" copy/part mystring skip tail
mystring -1]
10000000 cycles took 0:00:16.828
measuring method: [mystring: "123456" copy/part mystring at tail
mystring -1]
10000000 cycles took 0:00:16.86
measuring method: [mystring: "123456" mystring: head reverse remove head
reverse mystring]
10000000 cycles took 0:00:23.219
measuring method: [mystring: "123456" mystring: head remove at mystring
length? mystring]
10000000 cycles took 0:00:14.187
...so it looks 'head remove back tail mystring' is the fastest one for now.
feel free to add your different methods and post results here!
regards,
Cyphre
