functional programming - Purescript applicative does not execute -


this executes:

main =    ctx <- getcanvaselementbyid "stage" >>= getcontext2d   bs  <- initbranches   tick 0 ctx bs

but not:

main = tick 0 <$> (getcanvaselementbyid "stage" >>= getcontext2d)               <*> initbranches

however both compile, , understanding both mean same basic thing. why case? can use applicative syntax here (its more understandable imho)

this works

main =   <- (tick 0) <$> (getcanvaselementbyid "stage" >>= getcontext2d) <*> initbranches    b <-   fprint b 

main = join $ tick 0 <$> (getcanvaselementbyid "stage" >>= getcontext2d)                       <*> initbranches

the applicative creates nested eff, join resolves easily


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