Built-in casts for ltree

contrib/ltree includes text2ltree and ltree2text functions, but no
implicit casts. Is there any particular reason for this?

--- ltree.sql.in.orig Mon Jan 24 22:47:01 2005
+++ ltree.sql.in Mon Jan 24 22:58:40 2005
@@ -155,10 +155,14 @@
AS 'MODULE_PATHNAME'
LANGUAGE 'C' WITH (isstrict,iscachable);

+CREATE CAST (ltree AS text) WITH FUNCTION ltree2text(ltree) AS IMPLICIT;
+
CREATE FUNCTION text2ltree(text)
RETURNS ltree
AS 'MODULE_PATHNAME'
LANGUAGE 'C' WITH (isstrict,iscachable);
+
+CREATE CAST (text AS ltree) WITH FUNCTION text2ltree(text) AS IMPLICIT;

CREATE FUNCTION lca(_ltree)
RETURNS ltree
--
Jim C. Nasby, Database Consultant decibel(at)decibel(dot)org
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