Assertion or assert may refer to: Assertion (software development), a computer programming technique. assert.h, a header file in the standard library of the C programming language. Assertion definition language, a specification language providing a formal grammar to specify behaviour and interfaces for computer software.
Grass snakes prey mainly on amphibians, especially the common toad and the common frog, although they may also occasionally eat ants and larvae. Captive snakes have been observed taking earthworms offered by hand, but dead prey items are never taken.
For example, sand boas of Middle Eastern deserts primarily eat rodents, while desert-dwelling pythons, such as blackhead pythons, prefer lizards. Other snakes of the desert concentrate on smaller prey. Black-headed snakes primarily consume arthropods, such as insects, centipedes and scorpions.