Read a JSON number as a double, widening an integer-encoded value. vibe.d
serializes a whole-valued double (e.g. 5.0) as a JSON integer, so a value
the producer intended as a number can arrive as Json.Type.int_; clients that
expect a double would otherwise have to re-derive this widening themselves.
Returns j.get!double for a float, cast(double) j.get!long for an integer,
and throws for any non-numeric Json.
Read a JSON number as a double, widening an integer-encoded value. vibe.d serializes a whole-valued double (e.g. 5.0) as a JSON integer, so a value the producer intended as a number can arrive as Json.Type.int_; clients that expect a double would otherwise have to re-derive this widening themselves. Returns j.get!double for a float, cast(double) j.get!long for an integer, and throws for any non-numeric Json.