Crystal 0.6.0 has been released!
This release contains several fixes to the language as a whole.
Renames, and class/struct distinction
Function was renamed to Proc, to match Ruby’s name, but also because it’s not just a
function: it can have an associated closure context, so the new name reflects that better.
It’s also shorter to write.
Pointer and Tuple are now considered structs by the compiler, so to reopen them you
must do struct Pointer; ...; end. This doesn’t change anything, really, but makes everything
be consistent: structs are passed by value, classes are passed by reference. Both Pointer
and Tuple are passed by value, so it makes sense for them to be structs.
Thread-safe magic variabels
Crystal retains a few magic variables from Ruby: $~ (and the associated $1, $2, … variables) and $?.
Although they are magical and might look cryptic at first, once you learn them they become a valuable tool
for writing short, readable code.
Before this release these variables were global, meaning that they were also not thread-safe. Starting
from this release they are method-local, defined by, for example, String#=~ and Regex#===. You
can read the details of the implementation here.
Happy hacking! :-)