[R] Subsetting a list of lists using lapply

[Charles C. Berry]

On Fri, 20 Feb 2015, Aron Lindberg wrote:

> Hmm…Chuck’s solution may actually be problematic because there are several entries which at the deepest level are called “sha”, but that should not be included, such as:
>
>
>
>
>
> input[[67]]$content[[1]]$commit$tree$sha
>
>
>
>
> and
>
>
>
>
> input[[67]]$content[[1]]$parents[[1]]$sha
>
>
>
>
>
> it’s only the “sha” that fit the following subsetting pattern that should be included:
>
>
>
>
>
> input[[i]]$content[[1]]$sha[1]
>
>


This should be straightforward. Look at what grepl() is doing.

And look at what names(unlist(input)) yields.

You can either write a regular expression to handle this (perhaps 
"content.sha$") or write other grepl() expressions to select (or get rid 
of) the desired (or unwanted) pattern.

See ?grepl and the page on regular expression referenced there.

HTH,

Chuck