as_json(options = nil)public
A BigDecimal would be naturally represented as a JSON number. Most libraries, however, parse non-integer JSON numbers directly as floats. Clients using those libraries would get in general a wrong number and no way to recover other than manually inspecting the string with the JSON code itself.
That’s why a JSON string is returned. The JSON literal is not numeric, but if the other end knows by contract that the data is supposed to be a BigDecimal, it still has the chance to post-process the string and get the real value.
# File activesupport/lib/active_support/json/encoding.rb, line 192 def as_json(options = nil) to_s end