1. A method implemented in a computer, the method comprising: said computer receiving an invocation of a first macro and a variable as an argument for the first macro; subsequent to said receiving, said computer automatically identifying a second macro to be invoked to perform, on said variable, an operation identified by the first macro; wherein the first macro and the second macro have different names; wherein the second macro is defined within said computer to comprise first assembler instructions for use with at least variables of an element type identical to a corresponding type of the variable; said computer automatically expanding the second macro, using at least said first assembler instructions to generate second assembler instructions in an assembly language; and said computer using an assembler for said assembly language to generate object code, based at least on said second assembler instructions; wherein the second assembler instructions comprise at least one opcode which depends at least on said corresponding type of the variable.