The v18 beta introduces a new variable type: variant. Not surprisingly
there is already discussion about what it could possibly be useful for and
why it doesn't have more capabilities. We are who we are.
I have come across a clear case where it's a perfect solution.
Consider a collection of text and null values. Like so:
$tuple_col:=New collection("a";"b";"c";null;null;null;"z")
I want to iterate through the collection and concatenate the values into a
string.
$str:=""
For each ($element;$tpl_col)
If ($element#Null)
$str:=$str+$element
End if
$str:=$str+$delim
End for each
If this code is interpreted and not typed things are fine. As soon as I
declare $element as TEXT it throws an error when I hit a Null. If I declare
it as an object it throws an error when it hits a text. But if I declare
$element as C_VARIANT it's all good.
I suspect something like this is the motivation behind the C_VARIANT data
type to begin with. Otherwise accomplishing this loop would get
complicated. So here in 4D land C_VARIANT solves the problem of how we deal
with a stream of different data types. Like a collection or object
properties.
--
Kirk Brooks
San Francisco, CA
=======================
What can be said, can be said clearly,
and what you can’t say, you should shut up about
*Wittgenstein and the Computer *
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