Recipe for symlog scale

New to Julia
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1

I want to plot x/y data (lines) using a symlog scale. I wrote 2 functions to convert the data points and one to adapt the ticks. So basically I can do:

using Plots
x = collect(-10:0.01:10)
y = collect(-10:0.01:10)
plot(x, symlog(y,-3.0), yformatter=x->symlogformatter(x, -3.0))

demo

How can I extend the plot function to use the argument yscale = SymLog(-3) ?

The two crude functions look like this:

function symlog(x,n=-3) 
    result = zeros(size(x,1))
    for i in 1:size(x,1)
        result[i] = sign(x[i])*(log10(1+abs(x[i])/(10^n))) 
    end
    result
end

function symlogformatter(x,n)
    if sign(x) == 0
        "10^$(n)"
    else
        s = sign(x)==1 ? "+" : "-"
        nexp = sign(x)*(abs(x) + n)
        if sign(x) == -1
            nexp = -nexp
        end
        s*"10^$(nexp)"
    end
end
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