Examples showing that @eval is bad

mwe_nlp_noeval.jl

include("src/CUTEst.jl")

using CUTEst

function test(nlp; N = 100)
  n = Cint[nlp.meta.nvar]
  m = Cint[nlp.meta.ncon]
  x = zeros(nlp.meta.nvar)
  c = zeros(nlp.meta.ncon)
  io_err = Cint[0]

  for i = 1:N
    f = [0.0]
    ccall((:cutest_cfn_, "libHS35.so"), Void,
      (Ptr{Int32}, Ptr{Int32}, Ptr{Int32}, Ptr{Float64}, Ptr{Float64},
      Ptr{Float64}),
      io_err, n, m, x, f, c)
  end
end

nlp = CUTEstModel("HS35")
test(nlp, N=1)
test(nlp, N=100000)

mwe_standalone.jl

#include("src/CUTEst.jl")

#using CUTEst

io_err = Cint[0]

function test(nvar; N = 100)
  n = Cint[nvar]
  x = rand(nvar)

  for i = 1:N
    f = [0.0]
    ccall((:cutest_ufn_, "libROSENBR.so"), Void,
      (Ptr{Int32}, Ptr{Int32}, Ptr{Float64}, Ptr{Float64}),
      io_err, n, x, f)
  end
end

# Suppose libROSENBR.so and auxiliary .f files are available
funit = Int32(42)
outsdif = "OUTSDIF.d"
nvar = Cint[0]
ncon = Cint[0]

ccall((:fortran_open_, "libROSENBR.so"), Void,
    (Ptr{Int32}, Ptr{UInt8}, Ptr{Int32}),
    &funit, outsdif, io_err)
ccall((:cutest_cdimen_, "libROSENBR.so"), Void,
    (Ptr{Int32}, Ptr{Int32}, Ptr{Int32}, Ptr{Int32}),
    io_err, &funit, nvar, ncon)
x  = Array(Float64, nvar[1])
bl = Array(Float64, nvar[1])
bu = Array(Float64, nvar[1])
ccall((:cutest_usetup_, "libROSENBR.so"), Void,
    (Ptr{Int32}, Ptr{Int32}, Ptr{Int32}, Ptr{Int32}, Ptr{Int32}, Ptr{Float64},
    Ptr{Float64}, Ptr{Float64}),
    io_err, &funit, Cint[5], Cint[6], nvar, x, bl, bu)
ccall((:fortran_close_, "libROSENBR.so"), Void,
    (Ptr{Int32}, Ptr{Int32}), &funit, io_err)

test(nvar[1], N=1)
test(nvar[1], N=100000)