[Haskell-cafe] Using State monad with lens

[Michael Hull]

Hi,
I use the State monad in a lot of places, but when I use it with the lens
library, I find myself writing code like:

myFunc :: StateT MyState ([ResultType])
myFunc = do
   st <- get
   case st ^. some_property of
      True -> do
            my_value .= "Hello"
      True -> do
            my_value .= "Goodbye"

I want to do something based on a 'state-variable', but I have to write
'get' -- is there a pattern that allows me to avoid the intermediate 'st'
variable?
I want to write something like:

myFunc = do
   case (get ^. some_property) of
      True -> do
            my_value .= "Hello"
      True -> do
            my_value .= "Goodbye"

but that won't compile.

Best wishes,

Mike
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