RemoveFmtUnderscore remove underscore in format placeholder {abc_def_} => {abcdef}.

RemoveJsoncComments remove json comments.

ValueOrDefault returns the value if it is not empty, otherwise the default value.

VariableReplace Replace vairable placeholder like $(a.b.c) to value using map.

VariableReplaceFunc Replace vairable placeholder like $(a.b.c) to value using map function.