StringViews

This Julia package implements a new type of AbstractString, a StringView, that provides a string representation of any underlying array of bytes (any AbstractVector{UInt8}), interpreted as UTF-8 encoded Unicode data.

Unlike Julia's built-in String type (which also wraps UTF-8 data), the StringView type is a copy-free wrap of any AbstractVector{UInt8} instance, and does not take "ownership" of or modify the array. Otherwise, a StringView is intended to be usable in any context where you might have otherwise used String.

(In particular, as much as possible we try to implement efficient copy-free String-like operations on StringView, such as iteration and regular-expression searching, as long as the underlying UInt8 array is a contiguous dense array.)

For example:

julia> b = [0x66, 0x6f, 0x6f, 0x62, 0x61, 0x72];

julia> s = StringView(b) # does not make a copy
"foobar"

julia> collect(eachmatch(r"[aeiou]+", s))
2-element Array{RegexMatch,1}:
 RegexMatch("oo")
 RegexMatch("a")

julia> StringView(@view b[1:3]) # also works for subarrays, with no copy
"foo"

julia> abc = StringView(0x61:0x63) # and for other array types
"abc"

Other optimized (copy-free) operations include I/O, hashing, iteration/indexing, comparisons, parsing, searching, and validation. Working with a SubString of a StringView is similarly efficient.