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R/print.data.table.R

@@ -30,7 +30,7 @@ print.data.table = function(x, topn=getOption("datatable.print.topn"),
     # Other options investigated (could revisit): Cstack_info(), .Last.value gets set first before autoprint, history(), sys.status(),
     #   topenv(), inspecting next statement in caller, using clock() at C level to timeout suppression after some number of cycles
     SYS = sys.calls()
-    if (identical(SYS[[1L]][[1L]], print) ||
+    if (identical(SYS[[1L]][[1L]], print) || # this is what auto-print looks like, i.e. '> DT' and '> DT[, a:=b]' in the terminal; see #3029.
         ( length(SYS) >= 3L && is.symbol(thisSYS <- SYS[[length(SYS)-2L]][[1L]]) &&
           as.character(thisSYS) == 'source') ) { # suppress printing from source(echo = TRUE) calls, #2369
       return(invisible(x))