emoji_rx <- "[\\x{1f300}-\\x{1f5ff}\\x{1f900}-\\x{1f9ff}\\x{1f600}-\\x{1f64f}\\x{1f680}-\\x{1f6ff}\\x{2600}-\\x{26ff}\\x{2700}-\\x{27bf}\\x{1f1e6}-\\x{1f1ff}\\x{1f191}-\\x{1f251}\\x{1f004}\\x{1f0cf}\\x{1f170}-\\x{1f171}\\x{1f17e}-\\x{1f17f}\\x{1f18e}\\x{3030}\\x{2b50}\\x{2b55}\\x{2934}-\\x{2935}\\x{2b05}-\\x{2b07}\\x{2b1b}-\\x{2b1c}\\x{3297}\\x{3299}\\x{303d}\\x{00a9}\\x{00ae}\\x{2122}\\x{23f3}\\x{24c2}\\x{23e9}-\\x{23ef}\\x{25b6}\\x{23f8}-\\x{23fa}]"
x <- "I know \U0001F621\U0001F923s"
regmatches(x, gregexpr(emoji_rx, x, perl=TRUE))
## => [[1]]
## [1] "😡" "🤣"
## Or, to get them as single chunks
emoji_rx <- "[\\x{1f300}-\\x{1f5ff}\\x{1f900}-\\x{1f9ff}\\x{1f600}-\\x{1f64f}\\x{1f680}-\\x{1f6ff}\\x{2600}-\\x{26ff}\\x{2700}-\\x{27bf}\\x{1f1e6}-\\x{1f1ff}\\x{1f191}-\\x{1f251}\\x{1f004}\\x{1f0cf}\\x{1f170}-\\x{1f171}\\x{1f17e}-\\x{1f17f}\\x{1f18e}\\x{3030}\\x{2b50}\\x{2b55}\\x{2934}-\\x{2935}\\x{2b05}-\\x{2b07}\\x{2b1b}-\\x{2b1c}\\x{3297}\\x{3299}\\x{303d}\\x{00a9}\\x{00ae}\\x{2122}\\x{23f3}\\x{24c2}\\x{23e9}-\\x{23ef}\\x{25b6}\\x{23f8}-\\x{23fa}]+"
regmatches(x, gregexpr(emoji_rx, x, perl=TRUE))
## => [[1]]
## [1] "😡🤣"
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