Use hasName

[helske]

From R-devel: "Convenience function ‘hasName()’ has been added; it is intended to replace the common idiom ‘!is.null(x$name)’ without the usually unintended partial name matching. "

I have used the latter method several times in KFAS and the debugging has been pain... And due to partial name matching I have been resorting this kind of ugliness:
(!is.null(x[["a", exact = TRUE]]) || !is.null(x$alphahat))