I am designing a language where I want to use .. to define an integer range. The problem is that 0..10 is tokenized as the floats 0. and .10.
How do I allow support this syntax with flex? Is it is simple as making 0. an invalid float?
This is really up to how you define your lexer. If you define the ellipsis as being a token made up of two periods, and also define your floating point numbers correctly, there should not be a conflict. Just make sure the token for the ellipsis is defined first in your specification. And, yes, 0. should be an invalid float.