add bytes2hex(io, a) method #27124
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add bytes2hex(io, a) method #27124
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Travis Mac failure ( |
vtjnash
reviewed
May 16, 2018
| @@ -575,6 +580,11 @@ function bytes2hex(a::AbstractArray{UInt8}) | |||
| return String(b) | |||
| end | |||
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| bytes2hex(io::IO, a::AbstractArray{UInt8}) = | |||
| for x in a | |||
| print(io, Char(hex_chars[1 + x >> 4]), Char(hex_chars[1 + x & 0xf])) | |||
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write(io, hex_chars[1 + (x >> 4)]) would probably be faster, since it'll save us from needing to decode the Char into the stream
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Faster but wrong, unfortunately. Writing bytes directly assumes that io uses an ASCII-compatible encoding (#26286). We would need an ASCIIChar type to get both encoding-independence and maximum performance here.
vtjnash
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Fixes #27036.
I don't really care about allocating an extra string when calling
printon anSHA1object, but I can easily imagine cases where you might be writing a long block of hexadecimal text to a file and then it would be mildly annoying to be forced to allocate an extra string.Actually, the old code allocated two extra strings rather than one, because it wasn't using
StringVector. #27036 also mentioned UUID printing, but this doesn't go throughbytes2hexso I left it as allocating an extra string (I doubt it's a big deal in practice) but I did slightly clean up the code to use the samehex_charsarray asbytes2hex.