ANN LegibleLambdas.jl

Package Announcements
8

The culprit was relying on Base.@locals to fetch variable names and values which is slow and won’t be optimized away by the compiler. What I realized recently was that closures actually store the names and values of the bound variables in themselves, so there was no need for Base.@locals.

Here’s a minimal working example of the problem:

julia> f(x) = (Base.@locals(), y -> x + y)
f (generic function with 1 method)

julia> let x = Ref(1), y = Ref(2)
           @btime f($x[])[2]($y[])
       end
  103.571 ns (4 allocations: 608 bytes)
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