Appian expression rule strange behaviour

Question

Hello, Consider the following test code: 
 a!localVariables(
 local!Torerance_Name:"Mean",
 local!test_0: and(
 local!Torerance_Name = "Mean",
 "15.0"
 ),
 local!test_1: and(
 local!Torerance_Name = "Mean",
 "8.2"
 )
) Here test_1 has value : false and test_0 has value true. What is the cause of this? Please find the screenshot as follows:

Mike Schmitt · Answer

The and() function expects a list of boolean arguments. Neither the text value "15.0" or "8.2" are boolean values. My guess is that when the and() function is typecasting both of these to boolean, it gets as far as seeing that "15.0" starts with "1", which aliases to a value of "TRUE" in most contexts, and thus casts it as "TRUE"; and likewise when it sees that "8.2" does not start with "1", it gets cast as "FALSE". 
 Any chance you tested this out? 
 So to answer your first question: no, it's not an Appian bug. 
 To echo Stefan as usual, what are you trying to achieve when you put the "15.0" and "8.2" text values in this rule? If I could tell what your intended rationality was I'd love to help you come up with the appropriate expression, but I'm struggling to understand.

Shubham Aware · Answer

Appian casts strings to boolean and In Expression Strings beginning with "t", "T", "y", "Y", or "1" return true; all other strings return false. Remove the string values from and() or use explicit boolean comparisons.

amerayanaa709622 · Answer

I was trying to understand the issue using gpt ,in one of it's responses :

.... How to fix it:

If the goal is “non-zero value” plus the Torerance_Name being “Mean”, they should:

Use numeric types, not strings, when testing numbers
Or compare the string explicitly, e.g. check if the string is not "0" or not empty or convert it to number and see if it's > 0

Some example fixes:

Or if the value is coming in as a string, convert it:

Or if the string is just being tested for being non-empty or non-zero in string form:

Mike Schmitt · Answer

Sadly OP has seemingly no-showed this thread - I was greedily hoping for some validation on my correct answer from nearly 3 days ago 
 Funny, I never exactly realized that the casting works out that way for all strings beginning with "T" and "Y" as well. It makes sense in a way of course, though in situations like the original post here, when someone wanders into a "typecast as boolean" situation with no idea what's happening or why, it can produce some truly silly results

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Arabic	Hebrew	Polish
Bulgarian	Hindi	Portuguese
Catalan	Hmong Daw	Romanian
Chinese Simplified	Hungarian	Russian
Chinese Traditional	Indonesian	Slovak
Czech	Italian	Slovenian
Danish	Japanese	Spanish
Dutch	Klingon	Swedish
English	Korean	Thai
Estonian	Latvian	Turkish
Finnish	Lithuanian	Ukrainian
French	Malay	Urdu
German	Maltese	Vietnamese
Greek	Norwegian	Welsh
Haitian Creole	Persian

Appian expression rule strange behaviour

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I was trying to understand the issue using gpt ,in one of it's responses : .... How to fix it:

I was trying to understand the issue using gpt ,in one of it's responses : .... How to fix it:

I was trying to understand the issue using gpt ,in one of it's responses :

.... How to fix it:

I was trying to understand the issue using gpt ,in one of it's responses :

.... How to fix it: