[R] What is the best way to delete strings in a string list that that match certain pattern?

[Peng Yu]

On Fri, Nov 6, 2009 at 3:05 AM, Diez B. Roggisch <deets at nospam.web.de> wrote:
> Peng Yu schrieb:
>>
>> Suppose I have a list of strings, A. I want to compute the list (call
>> it B) of strings that are elements of A but doesn't match a regex. I
>> could use a for loop to do so. In a functional language, there is way
>> to do so without using the for loop.
>
> Nonsense. For processing over each element, you have to loop over them,
> either with or without growing a call-stack at the same time.
>
> FP languages can optimize away the stack-frame-growth (tail recursion) - but
> this isn't reducing complexity in any way.
>
> So use a loop, either directly, or using a list-comprehension.

What is a list-comprehension?