This statement evaluates the specified expression and compiles the following statements if the expression is equivalent to TRUE. Constant expressions are a subset of regular BASIC expressions, made up only of defined symbols (constants) and literals (i.e. no variables), and a limited set of pre-defined functions and operators:
| • | All arithmetic operators (+,-,/,*,**,^,MOD) |
| • | All logical operators (AND, OR, NOT) |
| • | Comparison operators (<, >, <=, >=, ==, <>, #) |
| • | All bitwise operators (AND, OR, NOT, NOR, XOR) |
| • | Arithmetic functions: int(),fix(),abs(),min,max |
| • | Scientific functions: exp(),sgn(),sqr(),sin(),cos(),tan(),atn(),fact() |
| • | String functions: +,left(),mid(),right(),[a,b],len(),instr(),asc(),chr(), str(),val(),rtrim(),edit(),strip(),pad(0 |
| • | File functions: lookup() |
Examples
++IF APPVER > 3
++IF CUSTOM$ = "MR. BIG"
++IF (APPVER > 3) AND (LOOKUP("xyz.bsi") # 0)
