Signatures can subset Int

[hwayne]

The following spec is accepted by Alloy:

 sig A in Int {}

By this guide, you should not be able to declare a signature as a subset of Int.

[pkriens]

@dnjackson can you comment?

[pkriens]

@dnjackson still waiting for your comment :-)

[nmacedo]

This has been allowed at least since version 4, as long as the "experimental" flag is set to true, which has been for all releases :) Likewise for String and seq/Int by the way. (There are a lot of features under this experimental flag, this should probably be revised eventually.)

Personally, I think it's useful to have sub-signatures of Int, what are the cons?