Reducing Maintenance with Layouts and Partials
So far in this chapter we’ve looked at templates as isolated chunks of code and HTML. But one of the driving ideas behind Rails is honoring the DRY principle and eliminating the need for duplication. The average website, though, has lots of duplication:
Many pages share the same tops, tails, and sidebars.
Multiple pages may contain the same snippets of rendered HTML (a blog site, for example, may display an article in multiple places).
The same functionality may appear in multiple places. Many sites have a standard search component or a polling component that appears in most of the sites’ sidebars.
Rails provides both layouts and partials that reduce the need for duplication in these three ...