join ( array array , string|default:',' _separator , default:true _nullIfEmptyString ) : string
Join elements of an array by a glue. ex: join(["a","b"]) retunrs "a,b".
Parameters
array
_separator (optional)
_nullIfEmptyString (optional)
[true|false|"ignore"]. If the entry is null, it is replacer by "". Avoid to have something like that : string1,null,string3 (behavior if false). Other possibility: set this parameter to "ignore", the null entry is simply ignored (string1,string3)