How to say $\mathrm{id}_A(x)$

Question

Given a set $A$, we have the so-called identity function which maps each $x\in A$ to $x$ itself: $$\mathrm{id}_A(x)=x.$$

Since I don't know where else I could ask this question, let me ask it here: How would you say "$\mathrm{id}_A(x)$"? Would one say something like "id A of x" or "identity of x" or "the identity function on A of x"?

Answer 1

If I had to read that out, I'd say, "identity sub A of x".