Double splat in method definition prevents declaring local variables with a type.

[da99]

Declaring local variables with a type seems to be a new feature, which might explain this odd behaviour below. It appears when a double splat is used in the method and the same Symbol for a key (e.g. place) is used for a local variable with a declared type:

def show(**attrs)
  place : String = "w" # Not recommended practice at the moment.
  puts place
end

show(name: "Bobby")  # This works.

show(name: "Bobby", place: "World") # This fails:
#
#in tmp.cr:2: variable 'place' already declared
#
#  place : String = "w"
#  ^~~~~

(Originally posted on stackoverflow)