What does $\int_\mathbb{R^d}$ means in terms of limits

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This might be a silly question, but please help me understand that does the limits of the following expression. The left-hand-side is the actual expression, while the right-hand-side is my understanding.

$$\displaystyle \large e^{-\lambda\int_\mathbb{R^d}(1-e^{-f(x)})dx} = e^{-\lambda\int_x^\infty(1-e^{-f(x)})dx}$$

(We are dealing with a 2D euclidean plane here.)