JuliaLang/julia — pull request #8578 by jakebolewski (2014-10-04 22:51:23+00:00)
Title: WIP: Free up curly brace syntax.

The fate of the `{}` syntax has been debated in #7941, #7128, #2488, #6739 and many other threads that I cannot dig up at the moment. My suggestion was outlined by Jeff in #8470. Whatever we decide to do, this change makes it easier to transition to allowing `[a, b]` to be non-concatenating (#3737) and regularization of `Dict` syntax #8521.

The parser should probably be changed to reject the `{}` array / dict syntax during the transition period. Would throwing an error be sufficient? This will be a hugely breaking change so I thought I would solicit some feedback before finishing that part of the PR.