Using `Limit` with the Option `Assumptions`

 Using `Limit` with the Option `Assumptions`

I want to calculate the following limit

$ $ L=\lim_{r \to 0} \left( 1 + r \frac{El^{‘}(r)}{El(r)} \right)$ $

by letting Mathematica to know

$ $ \lim_{r \to 0} \frac{El^{‘}(r)}{El(r)} = A $ $

where $ A$ is a constant. It is evident that we should have $ L=1$ .

I used the following

Limit[1 + (r Derivative[1][El][r])/El[r], r -> 0, 
Assumptions -> {Limit[Derivative[1][El][r]/El[r], r -> 0] == a}]

But it didn’t work.

What should I do?

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