Class | BigDecimal |
In: |
lib/active_support/json/encoding.rb
lib/active_support/core_ext/big_decimal/conversions.rb |
Parent: | Object |
YAML_TAG | = | 'tag:yaml.org,2002:float' |
YAML_MAPPING | = | { 'Infinity' => '.Inf', '-Infinity' => '-.Inf', 'NaN' => '.NaN' } |
DEFAULT_STRING_FORMAT | = | 'F' |
to_s | -> | _original_to_s |
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.
This emits the number without any scientific notation. This is better than self.to_f.to_s since it doesn‘t lose precision.
Note that reconstituting YAML floats to native floats may lose precision.