functional programming - Scala compiler not executing the values which are not returned -


i new scala. writing code , found unusual behaviour scala. had written code

for {   verification <- verifyreset(hash, timestamp, id)   resp = if (verification) {           setpassword(id, password)           setactive(id)           httpresponse(accepted, seq(location(empty withpath path / id)))   } else httpresponse(unauthorized) } yield resp

here setpassword , setactive used db operations. while testing found loop yielded resp(accepted) without executing setpassword , setactive. hypothesized since compiler doesn't need execute functions in-order return last statement, didn't execute them.

but then, wrote similar function behaved pretty different hypothesis,

r = if(true){      println("1st statement")      println("2nd statement")      2*3 }

i got r 6 (normal behavior), gave me output on console

1st statement 2nd statement

i didn't understand because in calculating 2*3 don't need execute println, why println executed?

your hypothesis wrong here.

it execute operations before returning last statement. the last statement returned default. there must other error

setpassword(id, password) setactive(id)


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