grep has a fixed = TRUE argument if you want to ignore all regexp's. On Sat, Nov 29, 2008 at 3:55 PM, Stavros Macrakis <[EMAIL PROTECTED]> wrote: > Hmm, this brings up an interesting question. What if the string I'm looking > for contains escape characters? For example, grep( paste( "^", "(ab)" ), > c("ab","(ab)") ) => c(1), not c(2). > > I couldn't find an equivalent to Emacs's regexp-quote, which would let me > write regexp.quote("(ab)") => "\\(ab\\)". The syntax of regular expressions > is complicated enough that this is not trivial. Is there perhaps a CRAN > package with regular expression utilities? > > -s > > On Sat, Nov 29, 2008 at 7:12 AM, Gabor Grothendieck > <[EMAIL PROTECTED]> wrote: >> >> > a <- 2:3 >> > b <- c("aaa 2 aaa", "2 aaa", "3 aaa", "aaa 3 aaa") >> > re <- paste("^(", paste(a, collapse = "|"), ")", sep = "") >> > grep(re, b, value = TRUE) >> [1] "2 aaa" "3 aaa" > >
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