Newton + LineSearch in Hot Loop: Reduce allocations

[DanielDoehring]

I really like the NLsolve.jl package in conjunction with LineSearches.jl - great stuff!

I have a scalar, relatively simple nonlinear equation that I can solve using

res = nlsolve(gamma -> f(gamma[1], bla, bla, bla),
              gamma -> j(gamma[1], bla, bla, bla),
              [gamma], method = :newton,  ftol = 2 * eps(RealT), iterations = 20,
              linesearch = LineSearches.BackTracking(order=3))
gamma = res.zero[1]

which works really well.
The issue is, however, that I get a couple allocations whenever I call this. Is there any way to reduce these by e.g. initalizing the problem once and then updating it later?

The functions f and g stay constant over time, although their arguments bla change over time.

Xref: https://discourse.julialang.org/t/newton-linesearch-in-hot-loop-reduce-allocations/122585