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Optimize encode32 #9

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4 changes: 2 additions & 2 deletions lib/ulid/constants.rb
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Original file line number Diff line number Diff line change
Expand Up @@ -12,10 +12,10 @@ module Constants

# Crockford's Base32. Alphabet portion is missing I, L, O, and U.
ENCODING = "0123456789ABCDEFGHJKMNPQRSTVWXYZ"

ENCODING_LIST = ENCODING.split('')
# Byte to index table for O(1) lookups when unmarshaling.
# We rely on nil as sentinel value for invalid indexes.
B32REF = Hash[ ENCODING.split('').each_with_index.to_a ]
B32REF = Hash[ ENCODING_LIST.each_with_index.to_a ]
end
end

52 changes: 26 additions & 26 deletions lib/ulid/generate.rb
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Expand Up @@ -24,34 +24,34 @@ def encode32
# decoded into the original bytes.

# 10 byte timestamp
output << ENCODING[(id[0]&224)>>5]
output << ENCODING[id[0]&31]
output << ENCODING[(id[1]&248)>>3]
output << ENCODING[((id[1]&7)<<2)|((id[2]&192)>>6)]
output << ENCODING[(id[2]&62)>>1]
output << ENCODING[((id[2]&1)<<4)|((id[3]&240)>>4)]
output << ENCODING[((id[3]&15)<<1)|((id[4]&128)>>7)]
output << ENCODING[(id[4]&124)>>2]
output << ENCODING[((id[4]&3)<<3)|((id[5]&224)>>5)]
output << ENCODING[id[5]&31]
output << ENCODING_LIST[(id[0]&224)>>5]
output << ENCODING_LIST[id[0]&31]
output << ENCODING_LIST[(id[1]&248)>>3]
output << ENCODING_LIST[((id[1]&7)<<2)|((id[2]&192)>>6)]
output << ENCODING_LIST[(id[2]&62)>>1]
output << ENCODING_LIST[((id[2]&1)<<4)|((id[3]&240)>>4)]
output << ENCODING_LIST[((id[3]&15)<<1)|((id[4]&128)>>7)]
output << ENCODING_LIST[(id[4]&124)>>2]
output << ENCODING_LIST[((id[4]&3)<<3)|((id[5]&224)>>5)]
output << ENCODING_LIST[id[5]&31]

# 16 bytes of entropy
output << ENCODING[(id[6]&248)>>3]
output << ENCODING[((id[6]&7)<<2)|((id[7]&192)>>6)]
output << ENCODING[(id[7]&62)>>1]
output << ENCODING[((id[7]&1)<<4)|((id[8]&240)>>4)]
output << ENCODING[((id[8]&15)<<1)|((id[9]&128)>>7)]
output << ENCODING[(id[9]&124)>>2]
output << ENCODING[((id[9]&3)<<3)|((id[10]&224)>>5)]
output << ENCODING[id[10]&31]
output << ENCODING[(id[11]&248)>>3]
output << ENCODING[((id[11]&7)<<2)|((id[12]&192)>>6)]
output << ENCODING[(id[12]&62)>>1]
output << ENCODING[((id[12]&1)<<4)|((id[13]&240)>>4)]
output << ENCODING[((id[13]&15)<<1)|((id[14]&128)>>7)]
output << ENCODING[(id[14]&124)>>2]
output << ENCODING[((id[14]&3)<<3)|((id[15]&224)>>5)]
output << ENCODING[id[15]&31]
output << ENCODING_LIST[(id[6]&248)>>3]
output << ENCODING_LIST[((id[6]&7)<<2)|((id[7]&192)>>6)]
output << ENCODING_LIST[(id[7]&62)>>1]
output << ENCODING_LIST[((id[7]&1)<<4)|((id[8]&240)>>4)]
output << ENCODING_LIST[((id[8]&15)<<1)|((id[9]&128)>>7)]
output << ENCODING_LIST[(id[9]&124)>>2]
output << ENCODING_LIST[((id[9]&3)<<3)|((id[10]&224)>>5)]
output << ENCODING_LIST[id[10]&31]
output << ENCODING_LIST[(id[11]&248)>>3]
output << ENCODING_LIST[((id[11]&7)<<2)|((id[12]&192)>>6)]
output << ENCODING_LIST[(id[12]&62)>>1]
output << ENCODING_LIST[((id[12]&1)<<4)|((id[13]&240)>>4)]
output << ENCODING_LIST[((id[13]&15)<<1)|((id[14]&128)>>7)]
output << ENCODING_LIST[(id[14]&124)>>2]
output << ENCODING_LIST[((id[14]&3)<<3)|((id[15]&224)>>5)]
output << ENCODING_LIST[id[15]&31]

output
end
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