Translator – Operand Processing (Change)

Previously, operands were processed (checking types and inserting conversion codes) after all of the operands were received. The operands are pushed to the done stack. Operators are temporarily pushed to the hold stack and are removed before a lower precedence operator is pushed to the hold stack (the method of rearranging operators according to their precedence).

Similarly for functions and arrays that are not processed until the matching closing parentheses token is received, at which time all the arguments or sub-scripts are on the done stack. No type checking can be performed for non-internal functions and arrays, so their operands are saved with (attached to) the array or function token.

A change has already been implemented for multiple list assignments where each assignment item (variable or sub-string) is checked as received, at either comma or equal tokens. Something similar can also be performed for internal functions, in fact, some logic has already been added that determines if a comma or closing parentheses token is valid after each argument. Logic can be added to also check the data type of the argument, adding conversion operators when necessary.

It has also been determined that for a binary operator, it data type specific code is needed on the hold stack based on the first operand of an operator (for possible error reporting). If necessary, a conversion code will be added at the same time. And it is now not necessary to keep the first operand on the done stack, so it can be popped. When the operator is emptied from the hold stack, only the second operand needs to be checked.

It is possible that the operator code may need to be changed from the code found based on the first operand. Currently there is only one operator that has more than one code with the same first operand data type but different data types for the second operand (Power and PowerMul, discussed here). The multiple table flag can be used to identify these type of operators (this is the same flag used to identify internal functions with different codes for the number of arguments). When set, the Translator will look for the correct code instead of inserting a conversion code.