Is there a case statement /function in Appian . or an if ...else if in rules exp

@diraj

As per my knowledge everyone use to have nested if by the way you have used ..
To Make it readability for code u can use rules rather than using plain condition which makes code clumsy.
That's a good question let's see others view on this ..!!!

Try the function choose()

@dhirajk Hi, fn!displayvalue() can be an option as well. Though the readability is bad, I would suggest leaving the code as is, because it may not be a great idea to pull the results of the each condition into an separate expression rule, as the expression rule in-turn consumes some time for initialisation, processing and returning the output which ultimately increases the total execution time. Doing so on need basis(for instance, when the conditional output is a frequently changing, or is reusable, or contains a huge piece of code) might be worth rather than just for sake of improving the readability.

An other option is to build a matrix in database but it really depends on the nature of the requirement.

choose() function acts like swich case !

I would suggest a combination of fn!choose and fn!displayvalue to simulate a "switch" case in Appian. fn!choose is like switch case - but with one caveat - the "key" should be a number - it does not allow text values or float values. So, you can use fn!displayvalue with fn!choose when the value which decides which branch to takes is not a number.

Example Snippet:
load(

/*local!statusCode will be 1 or 2 or -1
1 - Approved
2 - Rejected
-1 - Some invalid value*/
local!statusCode: fn!displayvalue(
ri!status,
{"Approved", "Rejected"},
{1,2},
-1
),

fn!choose(
local!statusCode,

{
/*code for choice1 */
},

{
/*code for choice2 */
}
)
)

As long as the rule doesn't return a list, an additional call to fn!choose() isn't required and requirement can be accomplished just by making use of fn!dislayvalue() as follows:


fn!displayvalue(
ri!status,
{
                    "Approved",
                    "Rejected"
          },
{
                    rule!myRuleForApprovedStatus(),
                    rule!myRuleForRejectedStatus()
          },
rule!myDefaultRule()
)

In case if the rules returns lists, fn!choose() can be used.

@sikhivahans, Good suggestion.

Hi Dhiraj Kumar,
There is one function "choose( index, choice1, choice2, … )", you can used it as switch case logic...


follow the following link for more details:
docs.appian.com/.../fnc_logical_choose.html

And for if_else

"if(condition,statement1, statement2)"
in above syntax if condition is true "statement1" will get executed else "statement2"

In these way you can used if_else in Appian