Allow “import”ing view engines.

[issuefiler]

express/lib/view.js

Lines 80 to 81 in 5c4f3e7

	// default engine export
	var fn = require(mod).__express

I import view engines, configure them with the imported instances,

then Express requires them, creating new clones of them, and they, the require’d instances that are in use, end up unconfigured.

See eta-dev/eta#113.

[dougwilson]

Hi @issuefiler Express will only require a view module if you didn't provide your existing instance to Express. If the view engine you are importing and configuring relies of some kind of state to be maintained, it is recommended to provide the view engine instance to Express directly instead of relying on the auto-require feature.