Leaves primary function can sometimes be modified other than photosynthesis in plants according to their habitat and morphology.
Spines are leaf modifications generally observed in desert plants like cactus, Agave and Opuntia. Spines in these plants help them to prevent evaporation.
Succulent leaves are leaf modifications present in desert plants like Aloe vera modified for water storage for the plant to survive in arid conditions.
Trap leaves are leaf modifications present in plants like pitcher plants. This meat-eating mode of nutrition provides pitcher plants with the nutrients they fail to obtain from the soil - like nitrogen and phosphorus.
Phyllode is a leaf modification found plants like Australian Acacia. The leaves of these plants are short-lived and hence their petiole enlarges to form the phyllode and performs photosynthesis.