The Go language has a strong type system built into the language. The
types
package corrals named types into a single package that is terminal in
go
's import graph. The types
package should not have any downstream
dependencies. Each subsystem that defines its own set of types exists in its
own file, but all types are defined in the same package.
Everything should be made as simple as possible, but not simpler.
string
is a useful container and underlying type for identifiers, however
the string
type is effectively opaque to the compiler in terms of how a
given string is intended to be used. For instance, there is nothing
preventing the following from happening:
// `map` of Widgets, looked up by ID
var widgetLookup map[string]*Widget
// ...
var widgetID string = "widgetID"
w, found := widgetLookup[widgetID]
// Bad!
var widgetName string = "name of widget"
w, found := widgetLookup[widgetName]
but this class of problem is entirely preventable:
type WidgetID string
var widgetLookup map[WidgetID]*Widget
var widgetName
TL;DR: intentions and idioms aren't statically checked by compilers. The
types
package uses Go's strong type system to prevent this class of bug.