Retrieving an instance of an enum using a string

General Usage
7 
@enum LogLevel begin
    LL_INFO
    LL_DEBUG
end

Please also note from

Base.tryparse(E::Type{<:Enum}, str::String) =
    let insts = instances(E) ,
        p = findfirst(==(Symbol(str)) ∘ Symbol, insts) ;
        p !== nothing ? insts[p] : nothing
    end

using Test
@testset "now" begin
    @test tryparse(LogLevel, "LL_INFO") == LL_INFO
    @test tryparse(LogLevel, "ll_info") == nothing
    @test tryparse(LogLevel, "INFO") == nothing
    @test tryparse(LogLevel, "info") == nothing
end

Those possibles evolutions :

Base.tryparse(E::Type{<:Enum}, str::String; prefix::String="") =
    let eq(x, e) = lowercase(prefix*x) == lowercase(e) ,
        # eq could be statically dispatchable according to some enum surface lang traits
        insts = instances(E) ,
        p = findfirst(insts .|> string) do e; eq(str,e) end;
        p !== nothing ? insts[p] : nothing
    end

@testset "meanwhile" begin
    @test tryparse(LogLevel, "LL_INFO") == LL_INFO
    @test tryparse(LogLevel, "ll_info") == LL_INFO
    @test tryparse(LogLevel, "INFO"; prefix="LL_") == LL_INFO
    @test tryparse(LogLevel, "info"; prefix="LL_") == LL_INFO
end

particulaly considering Solving the drawbacks of @enum