How do I accomplish string manipulation during synthesis?

Hello everyone and thanks in advance for your replies.

Here's the situation. I coded up a fairly lengthy chuck of vhdl using std.textio.read and std.textio.write that parses up a couple of strings passed as generics into the entity. Now I know that textio is not synthesizable, but I used the statements in functions to interpret the strings and set constants in the entity. I just found out that the read / write functions are not executed at all. I could write my own version using 'new' and 'deallocate,' but those commands are not executed during synthesis either.

The one solution I have thought of is to use strings and integer index values as pointers and pass them back and forth. However, this is ugly to say the least.

Is there any other alternative that is VHDL only? Is there a pre-existing solution for this problem where read/write can be used in functions to set values for constants during synthesis?