[akkartik]

It's a toy like several others mentioned in this thread, but this language I worked on has ultra powerful lisp macros (f-exprs), guesses parens from indentation, provides infix, and supports imperative programming as well as Arc: http://akkartik.name/post/wart. Here's an example showing off all these features: https://gist.github.com/akkartik/4320819

[dkersten]

So, if you leave out parentheses it uses indentation and switches to infix?

[akkartik]

No, the two are independent. The rules for parentheses:

1. Multi-word lines without leading parens are grouped with later indented lines.

2. Indentation is not sensitive inside parens.

More info, unpacking the implications: https://github.com/akkartik/wart/blob/47e3572a29/004optional...

Infix works by using a disjoint set of 'operator characters' that isn't available to prefix symbols. More info: https://github.com/akkartik/wart/blob/47e3572a29/006infix