default to num instead of variable for toString (#1977)

* default to num instead of variable for toString

* to text instead of toString

* converToText

docs/reference/text/convert-to-text.md

@@ -0,0 +1,7 @@
+# convert to text
+
+Converts a value into a text representation.
+
+```sig
+convertToText(123)
+```