Expression Try Tag not Found Failover

Ignition
1

I have an expression on an INT tag in a UDT that is using binEnc() to combine some bits like so

binEnc(
{[.]1},
{[.]2},
try({[.]3},0),
try({[.]4},0),
try({[.]5},0),
try({[.]6},0)
)

In this instance, only 1 and 2 exist. So, shouldn't 3, 4, 5, and 6 fail over to 0? My tag throws an error, saying the tag is not found. Shouldn't that error failover?

2

Can you show the relevant UDT structure?

3

This is the INT with the expression.

image

If I use

binEnc(
{[.]1},
{[.]2},
if(isNull({[.]3}),0,{[.]3}),
if(isNull({[.]4}),0,{[.]4}),
if(isNull({[.]5}),0,{[.]5}),
if(isNull({[.]6}),0,{[.]6})
)

instead I get the result I want. I thought the try would behave the same and catch the null.

4

I don't know, but wouldn't an INT have all 32 bits defined?

1 Like
5

The rest would be 0 (implicit). Just combining these 6 into an INT (max 63) which can still be represented by a 32 bit

6

This is more readable

binEnc(
	{[.]1},
	{[.]2},
	coalesce({[.]3}),0),
	coalesce({[.]4}),0),
	coalesce({[.]5}),0),
	coalesce({[.]6}),0),
)
2 Likes
7

Ya, that's what I was trying to do with the try! Just using the wrong function.

Thanks!

1 Like