ConfigMergeable

Marker for types whose instances can be merged, that is Config and
ConfigValue. Instances of Config and ConfigValue can
be combined into a single new instance using the
withFallback() method.
''Do not implement this interface''; it should only be implemented by
the config library. Arbitrary implementations will not work because the
library internals assume a specific concrete implementation. Also, this
interface is likely to grow new methods over time, so third-party
implementations will break.
class Object
trait Matchable
class Any

Value members

Methods

Returns a new value computed by merging this value with another, with
keys in this value "winning" over the other one.
This associative operation may be used to combine configurations from
multiple sources (such as multiple configuration files).
The semantics of merging are described in the
spec for HOCON.
Merging typically occurs when either the same object is
created twice in the same file, or two config files are both loaded. For
example:
{{{
foo = { a: 42 }
foo = { b: 43 }
}}}
Here, the two objects are merged as if you had written:
{{{
foo = { a: 42, b: 43 }
}}}
Only [[ConfigObject]] and [[Config]] instances do anything in
this method (they need to merge the fallback keys into themselves). All
other values just return the original value, since they automatically
override any fallback. This means that objects do not merge "across"
non-objects; if you write
object.withFallback(nonObject).withFallback(otherObject),
then otherObjectwill simply be ignored. This is an
intentional part of how merging works, because non-objects such as
strings and integers replace (rather than merging with) any prior value:
{{{
foo = { a: 42 }
foo = 10
}}}
Here, the number 10 "wins" and the value of foo would be
simply 10. Again, for details see the spec.
Value Params
other
an object whose keys should be used as fallbacks, if the keys
are not present in this one
Returns
a new object (or the original one, if the fallback doesn't get
used)