diff --git a/R/nargin.R b/R/nargin.R
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+#' @title Number of function input arguments
+#' @description Returns the number of arguments passed to the parent function
+#' @return An integer
+#' @author Waldir Leoncio
+#' @note This function only makes sense inside another function
+nargin <- function() {
+	# FIXME: returning 0 because it is using its own envir instead of parent's
+	print(parent.env(environment()))
+	length(as.list(match.call(envir = parent.env(environment())))) - 1
+	# length(ls(envir=parent.env(environment()))) - 1
+}
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