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An one-liner Base64 Encoder in D. Decoder : https://gist.github.com/alphaKAI/9f11414b862dacf5fef4227723b904de
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import std.algorithm, | |
std.string, | |
std.ascii, | |
std.range, | |
std.conv; | |
import std.stdio; | |
R delegate(Args) Z(R, Args...)(R delegate(R delegate(Args), Args) f){ | |
return (Args args) => f(Z(f), args); | |
} | |
string encode(T)(T data) { | |
return | |
(convb => | |
(table => | |
(converted => | |
(binaries => | |
(bLen => | |
(prepared => | |
(pLen => | |
(quotients => | |
pLen % 4 == 0 | |
? quotients | |
: quotients ~ (remainds => | |
remainds.map!(remain => | |
table[remain] | |
).array.join ~ repeat("=", 4 - (pLen % 4)).join | |
)(prepared[($ - (pLen % 4))..$]) | |
)( | |
(pLen / 4).iota.map!(i => | |
(j => | |
4.iota.map!(k => | |
table[prepared[j + k]] | |
).array.join | |
)(i * 4) | |
).array.join | |
) | |
)(prepared.length) | |
)( | |
(quotients => | |
bLen % 6 == 0 | |
? quotients | |
: quotients ~ (remainds => | |
remainds ~ repeat("0", 6 - remainds.length).join | |
)(binaries[($ - (bLen % 6))..$]) | |
)((bLen / 6).iota.map!(i => binaries[(i * 6)..((i + 1) * 6)]).array) | |
) | |
)(binaries.length) | |
)(converted.join) | |
)( | |
data.map!(i => | |
(e => | |
e.length == 8 | |
? e | |
: repeat("0", 8 - e.length).join ~ e | |
)(convb(i, 2))).array | |
) | |
)( | |
(charset => | |
assocArray( | |
zip( | |
charset.length.iota.map!(i => | |
(e => | |
e.length == 6 | |
? e | |
: repeat("0", 6 - e.length).join ~ e | |
)(convb(i, 2))), | |
charset)) | |
)((uppercase ~ lowercase ~ digits ~ "+/").split(string.init)) | |
) | |
)((ulong N, int base) => | |
(convbM => | |
convbM(N, N, [], base) | |
)(Z((string delegate(ulong, ulong, ulong[], int base) convbM, ulong N, ulong tmp, ulong[] stack, int base) => | |
tmp ? convbM(N, tmp / base, stack ~ (tmp % base), base) : stack.reverse.map!(e => e.to!string).join))); | |
} | |
void main() { | |
import std.stdio; | |
writeln(encode("ABCDEFG")); | |
assert("QUJDREVGRw==" == encode("ABCDEFG")); | |
} |
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