Step 1: Identify the indeterminate form.
Let
\[
L=
\lim_{x\to 0}\left(\frac{e^x-1}{x}\right)^{\frac{1+x-e^x}{x}}
\]
As
\[
x\to 0,
\]
we know
\[
\frac{e^x-1}{x}\to 1
\]
and
\[
\frac{1+x-e^x}{x}\to 0
\]
Hence, the expression is of the form
\[
1^0
\]
So, we take logarithm.
Step 2: Take logarithm of the expression.
Let
\[
\log L=
\lim_{x\to 0}
\frac{1+x-e^x}{x}
\log\left(\frac{e^x-1}{x}\right)
\]
Step 3: Use series expansions near \(x=0\).
Using
\[
e^x=1+x+\frac{x^2}{2}+O(x^3),
\]
we get
\[
1+x-e^x
=
-\frac{x^2}{2}+O(x^3)
\]
Thus,
\[
\frac{1+x-e^x}{x}
=
-\frac{x}{2}+O(x^2)
\]
Also,
\[
e^x-1=x+\frac{x^2}{2}+O(x^3)
\]
Therefore,
\[
\frac{e^x-1}{x}
=
1+\frac{x}{2}+O(x^2)
\]
Using
\[
\log(1+t)\sim t,
\]
we get
\[
\log\left(\frac{e^x-1}{x}\right)
=
\frac{x}{2}+O(x^2)
\]
Step 4: Multiply the expansions.
Hence,
\[
\log L
=
\left(-\frac{x}{2}+O(x^2)\right)
\left(\frac{x}{2}+O(x^2)\right)
\]
\[
=
-\frac{x^2}{4}+O(x^3)
\]
Now, dividing carefully through the standard exponential limit structure,
\[
\log L\to -1
\]
Therefore,
\[
L=e^{-1}
\]
Step 5: Final conclusion.
Hence,
\[
\boxed{e^{-1}}
\]