Lack of default constructor is hurting Go

#go #opinion

How many times have you written a factory function just to initialize a struct with proper default value?

For example:

// PagingOption ...
type PagingOption struct {
    Page int
    Size int
}

We usually want BOTH to have default values. Let's say page=1&size=25, but anywhere we want to use PagingOption we are either

Write and use a factory function which properly build a PagingOption
Write and use an Init function which properly build a PagingOption
Instantiate using object literal and fill it with default value
Validate PagingOption in every consumer and fallback to default value if necessary

Option 1 forces all developer to remember not to use new(PagingOption) or PagingOption{}.
Option 2 forces all developer to remember calling .Init after initializing PagingOption
Options 3 forces all developer to know what is the agreed default values.
Options 4 forces all developer to remember checking default value before using the PagingOption