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Unify the translatable strings.

Co-authored-by: Michael Chirico <[email protected]>

Author: aitap

src/between.c

@@ -31,10 +31,16 @@ SEXP between(SEXP x, SEXP lower, SEXP upper, SEXP incbounds, SEXP NAboundsArg, S
 
   // check before potential coercion which ignores methods, #7164
   if (INHERITS(x, char_integer64)) {
-    if (!INHERITS(lower, char_integer64) || !INHERITS(upper, char_integer64))
-      error(_("x is integer64 but lower and/or upper are not.")); // e.g. between(int64, character, character)
-  } else if (INHERITS(lower, char_integer64) || INHERITS(upper, char_integer64))
-    error(_("x is not integer64 but lower and/or upper is integer64. Please align classes."));
+    if (!INHERITS(lower, char_integer64))
+      error(_("x is integer64 but %s is not."), "lower"); // e.g. between(int64, character, character)
+    if (!INHERITS(upper, char_integer64))
+      error(_("x is integer64 but %s is not."), "upper"); // e.g. between(int64, character, character)
+  } else {
+    if (INHERITS(lower, char_integer64))
+      error(_("x is not integer64 but %s is. Please align classes."), "lower");
+    if (INHERITS(upper, char_integer64))
+      error(_("x is not integer64 but %s is. Please align classes."), "upper");
+  }
 
   if (isInteger(x)) {
     if ((isInteger(lower) || fitsInInt32(lower)) &&