The result of an expression must be an absolute number, or else an offset into a particular section. This is compatible with other assemblers. An integer expression is one or more arguments delimited by operators . Arguments Arguments are symbols, numbers or subexpressions. NNN is a signed, 2's complement 32 bit integer.
Numbers are usually integers.
A number can be a flonum or bignum. In this case, you are warned that only the low order 32 bits are used, and as pretends these 32 bits are an integer. You may write integer-manipulating instructions that act on exotic constants, compatible with other assemblers. Prefix operators are followed by an argument. Infix operators appear between their arguments.