Eval and Callp are the only two exceptions to the rule that each free-format line must start with an operation code.
Since you can leave these two opcodes out, you should for cleaner, more readable code.
Noncompliant code example
Eval Regpay = hours * perHour;
Callp calcTax();
Compliant solution
Regpay = hours * perHour;
calcTax();
