How do make a string from pointer to a piece memory that is in the format of a string?

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I am writing a fast serializer of strings onto disk. What I found was that a String’s memory structure is very simple. It’s basically a UInt64 followed by bytes. The first UInt64 indicates the length of the string, and the subsequent bytes are the content of a string.

E.g…

a = reinterpret(UInt8, [2])
a = vcat(a, UInt8[63, 64])

b = String(UInt8[63, 64])

b_structure = unsafe_load.(pointer(b)-8, 1:10)

b_structure == a
a = reinterpret(UInt8, [2])
a = vcat(a, UInt8[63, 64])

b = String(UInt8[63, 64])

b_structure = unsafe_load.(pointer(b)-8, 1:10)

b_structure == a

Notice in the above b is a string. But a is just some array of UInt. If I convert the string b to its binary representation, you will see that they have the same structure.

Now if I want to make the content start from pointer(a) into a String. How do I do that? I need a no-copy solution! So unsafe_string doesn’t fit the bill here.

Thanks!!

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