time-translate.py

#!/usr/bin/env python

import re
import time
import contextlib

@contextlib.contextmanager
def timeit():
    start = time.time()
    try:
        yield
    finally:
        end = time.time()
        print(f"total time: {end - start:.2f}s")


with open("hashes") as f:
    hashes = f.read().strip().split()


N = 10000
translator = str.maketrans("oliu", "0189")

bytes_translator = bytes.maketrans(b"oliu", b"0189")

arr_translator = list(range(128))
for k, v in zip("oliu", "0189"):
    arr_translator[ord(k)] = ord(v)


print("dict translate")
with timeit():
    for i in range(N):
        for h in hashes:
            h.translate(translator)

print()
print("bytes translate")
with timeit():
    for i in range(N):
        for h in hashes:
            h.translate(bytes_translator)

print()
print("arr translate")
with timeit():
    for i in range(N):
        for h in hashes:
            h.translate(arr_translator)

print()
print("4 replace calls")
with timeit():
    for i in range(N):
        for h in hashes:
            h = h.replace("o", "0").replace("l", "1").replace("i", "8").replace("u", "9")


print()
print("replace loop")
with timeit():
    for i in range(N):
        for h in hashes:
            for k, v in ("o0", "l1", "i8", "u9"):
                h = h.replace(k, v)


print()
print("replace zip loop")
with timeit():
    for i in range(N):
        for h in hashes:
            for k, v in zip("oliu", "0189"):
                h = h.replace(k, v)


t = {"o": "0", "l": "1", "i": "8", "u": "9"}

def replacer(m):
    g = m.group(0)
    return t.get(g, g)

print()
print("re.sub")
with timeit():
    for i in range(N):
        for h in hashes:
            re.sub(r"[oliu]", replacer, h)

very hard to beat just 4 chained replace calls:

> ./time-translate.py
dict translate
total time: 1.95s, 1,026,757/s

bytes translate
total time: 0.94s, 2,134,411/s

arr translate
total time: 0.92s, 2,183,725/s

4 chained replace calls
total time: 0.47s, 4,223,516/s

4 replace calls with assignment
total time: 0.61s, 3,264,245/s

replace loop
total time: 1.18s, 1,700,889/s

replace zip loop
total time: 1.29s, 1,553,982/s

re.sub
total time: 2.56s, 780,669/s