Try Operator

Try Operator

• The try operator safeguards against abnormal execution, which means saving programs that send messages to uninitialized variables.

• The compiler must have enough safeguards so that sending a method to an object that doesn't respond to it may never happen, thus making the try operator not applicable.

• Grammar

try_op : expr '~>' expr?
       ;

• Examples:

let next_value_of_x = x.next() ~> 0 # returns the next value of x or 0 if it fails
obj.do_something() ~>               # do_something() or, if it fails, do nothing.