R function that creates a QR code and can convert it to unicode, including emoji, thanks to {qrcode}

qr2uni.R

# See also Terence Eden
#   https://shkspr.mobi/blog/2020/12/a-qr-code-built-from-emoji/

install.packages("qrcode")  # if not already installed

qr2uni <- function(string,           # string to encode
                   uni_0 = "\U2B1C", # large white square emoji
                   uni_1 = "\U2B1B", # large black square emoji
                   plot = FALSE      # plot image of the QR too 
                   ) {
  
  qr_mat <- qrcode::qrcode_gen(
    string,
    dataOutput = TRUE,
    plotQRcode = plot
  )
  
  y <- gsub(0, uni_0, qr_mat)
  z <- gsub(1, uni_1, y)
  
  m <- matrix(z, nrow = sqrt(length(z)), ncol = sqrt(length(z)))
  
  for (i in 1:nrow(m)) {
    cat(m[i, ], "\n")
  }
  
}

qr2uni("https://www.rostrum.blog/")

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