evaluation - Does function call via @ ignore HoldFirst attribute?

I was trying to test whether using func[x,y] is the same as func[#,y]&@x:

SetAttributes[test, HoldFirst]
test[1 + 2 - 3, 5 - 5]

test[#, 5 - 5] &@(1 + 2 - 3)

test[1 + 2 - 3, 0]

test[0, 0]

So apparently, HoldFirst is ignored in the second case. Why is it so? Is the argument of @ evaluated before actually being passed?

Answer

andre has given a good answer. I will add a little further clarification. The function f[#]& is a different function than the function f and does not have its attributes. It is the short form of

Function[x, f[x]]

Assume

Clear[f]; SetAttributes[f, HoldFirst]

has been evaluated. Even though f is HoldFirst, both

Function[x, f[x]][1 + 1]

and

Function[x, f[x]] @ (1 + 1)

give

f[2]

When the pure function is also given the attribute HoldFirst, evaluation goes as you expect.

Function[x, f[x], HoldFirst] @ (1 + 1)

f[1 + 1]

Comments

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