> The difference is the syntax is structured more like Java's `try` and `catch` blocks

Which is a big plus, but the most interesting part to me is the "if" behavior you implemented.

  !if { foobar } then { ... }

Which basically translate to Bash (without STDOUT/STDERR handling):

   foobar
   if [ $? -ne 0 ] then ... fi

This is like 99% of my use cases when I'm writing scripts...

> As for testing, [...] they explain the syntax but not how nor why you might want to use it.

When I saw the examples, I immediately thought of "validation scripts" that would assert that an environment respects some specification (like the configure script from autotools ?)

> but man this post is already lengthy hehe

I enjoyed the details :)