The assembler processes the instructions and expressions of the conditional assembly language during conditional assembly processing. Then, at assembly time, it processes the generated instructions. Conditional assembly instructions, however, are not processed after conditional assembly processing is completed.
The conditional assembly language is more versatile when you use it to interact with symbolic parameters and the system variable symbols inside a macro definition. However, you can also use the conditional assembly language in open code; that is, code that is not within a macro definition.