What are the main syntax changes in Ruby 1.9?

Question

Also, I'm wondering what effect upgrading to Ruby 1.9 would have on legacy code from version 1.86. Is the new version backwards compatible?

Answer 1

I guess that depends on what version you're looking to maintain compatibility with. The CHANGELOG describes the major revisions since the last update including syntax changes, enhancements and bugfixes

Answer 2

Some things are backwards compatible, but many aren't.

For a near complete overview of all the changes (including examples) in 1.9.x, check out Eigenclass's blog.

Answer 3

Sam Ruby has a good slideshow of the major changes: Ruby 1.9: What to Expect

Just to highlight a few things that could break your code:

• Single character strings
• {"a", "b"} no longer makes a hash
• Block variables now shadow local variables