module JRuby

module Type

# Helper method to coerce a value into a specific class.

# Raises a TypeError if the coercion fails or the returned value

# is not of the right class.

# (from Rubinius)

def self.coerce_to(obj, cls, meth)

return obj if obj.kind_of?(cls)

begin

ret = obj.__send__(meth)

rescue Exception => e

raise TypeError, "Coercion error: #{obj.inspect}.#{meth} => #{cls} failed:\n" \

"(#{e.message})"

end

raise TypeError, "Coercion error: obj.#{meth} did NOT return a #{cls} (was #{ret.class})" unless ret.kind_of? cls

ret

end

def self.coerce_to_int(obj)

coerce_to(obj, Integer, :to_int)

end

def self.coerce_to_ary(obj)

coerce_to(obj, Array, :to_ary)

end

def self.coerce_to_str(obj)

coerce_to(obj, String, :to_str)

end

def self.is_array?(obj)

coerce_to(obj, Array, :to_ary) if obj.respond_to? :to_ary

end

end

end