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Co-authored-by: Yihui Xie <xie@yihui.name>

R/utils.R

@@ -52,27 +52,22 @@ update_unicode_latex <- function() {
     "\\Micro", "\\times", "\\eth", "\\div", "\\bullet",
     "\\vec", "\\eqcolon", "\\square", "\\blacksquare"
   )), , drop = FALSE]
-  row.names(tbl) <- NULL
-
-  rows <- lapply(
-    seq_len(nrow(tbl)),
-    function(i) {
-      sprintf(
-        '  c(unicode = "%s", latex = "%s", int = %d)',
-        tbl$unicode[i],
-        gsub("\\", "\\\\", tbl$latex[i], fixed = TRUE),
-        tbl$int[i]
-      )
-    }
+  rows <- paste(
+    tbl$unicode,
+    gsub("\\", "\\\\", tbl$latex, fixed = TRUE),
+    sprintf("%d", tbl$int),
+    sep = ", "
   )
 
   writeLines(c(
     "# Generated by R/utils.R: do not edit by hand",
     "# Please run update_unicode_latex() to regenerate this file",
     "",
-    "unicode_latex <- data.frame(rbind(",
-    paste(rows, collapse = ",\n"),
-    "), stringsAsFactors = FALSE)",
+    "unicode_latex <- matrix(c(",
+    paste0("  ", rows, collapse = ",\n")
+    "), ncol = 3, byrow = TRUE)",
+    "unicode_latex <- as.data.frame(unicode_latex)",
+    'names(unicode_latex) <- c("unicode", "latex", "int")',
     "",
     "unicode_latex$int <- as.integer(unicode_latex$int)"
   ), con = "R/unicode_latex.R")