2frac (problem 3.3.1)

Specification

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\[\begin{array}{l} \\ \frac{1}{x + 1} - \frac{1}{x} \end{array} \]
(FPCore (x) :precision binary64 (- (/ 1.0 (+ x 1.0)) (/ 1.0 x)))
double code(double x) {
	return (1.0 / (x + 1.0)) - (1.0 / x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (1.0d0 / (x + 1.0d0)) - (1.0d0 / x)
end function
public static double code(double x) {
	return (1.0 / (x + 1.0)) - (1.0 / x);
}
def code(x):
	return (1.0 / (x + 1.0)) - (1.0 / x)
function code(x)
	return Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(1.0 / x))
end
function tmp = code(x)
	tmp = (1.0 / (x + 1.0)) - (1.0 / x);
end
code[x_] := N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(1.0 / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{x + 1} - \frac{1}{x}
\end{array}

Reproduce

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herbie shell --seed 2024283 
(FPCore (x)
  :name "2frac (problem 3.3.1)"
  :precision binary64

  :alt
  (! :herbie-platform default (/ 1 (* x (- -1 x))))

  (- (/ 1.0 (+ x 1.0)) (/ 1.0 x)))

Please file a bug report with this information.

Backtrace

eprintf: format string requires 0 arguments, given 1; arguments were: '(#s(si 0 1) #s(si 1 4))LC
err-lsts->split-indices/home/nightlies/herbie/zane-regimes-old/src/core/regimes.rkt2190
option-on-expr/home/nightlies/herbie/zane-regimes-old/src/core/regimes.rkt1200
infer-splitpoints/home/nightlies/herbie/zane-regimes-old/src/core/regimes.rkt560
loop/home/nightlies/herbie/zane-regimes-old/src/core/regimes.rkt412
make-regime!/home/nightlies/herbie/zane-regimes-old/src/core/mainloop.rkt3500
extract!/home/nightlies/herbie/zane-regimes-old/src/core/mainloop.rkt790
run-improve!/home/nightlies/herbie/zane-regimes-old/src/core/mainloop.rkt450
get-alternatives/report/home/nightlies/herbie/zane-regimes-old/src/api/sandbox.rkt1860
(unnamed)/home/nightlies/herbie/zane-regimes-old/src/api/sandbox.rkt2826
(unnamed)/usr/share/racket/pkgs/profile-lib/main.rkt4010
profile-thunk/usr/share/racket/pkgs/profile-lib/main.rkt90
(unnamed)/usr/share/racket/collects/racket/engine.rkt4224