Translator – Command Expression Type

There was a problem getting the data type for the token on top of the command stack. There is no issue with assignment tokens as they contain a data type (they are just assignment operators put on the command stack).

A while back, a new field was added to the Table entries for the expression type with possible values of None, Numeric, String and Any to be used with command entries. The idea at the time was that this would be used for the expression type checking (for the generation of the correct error messages). However, this field was not being used (the original expression type code added at the time was abandoned because it had too many problems – it is currently commented).

This first attempt at the current problem was to use this expression type and convert it into a data type (None/Any to None, Numeric to Double, and String to String). The only place this was used was in the new get expression data type routine for commands. But this wasn't working for assignment commands (which were operators and their entries didn't have the expression type set – the data type in the expression information structure had the return value).

So it was concluded that the expression type field should be removed and the data type moved back from the expression information structure into the main entry structure (where it was originally). When the Parser finds and creates a command token, it sets the data type of the token to data type from the table entry. Currently for all tokens, the Parser was getting the data type from the expression information structure or none if there was no structure (as is the case for commands).